----

----

| April 28, 2010 |   |   | Analyst Contact: | Andrew Ziola |
|----------------|--------|--------|------------------|--------------|
|           |   |   |             | 918-588-7163 |
|           |   |   | Media Contact:   | Brad Borror  |
|           |   |   |             | 918-588-7582 |

----

| ·   | Operating income of $120.2 million, compared with $124.8 million in the first quarter last year; |
|--------------------|--------------------------------------------------------------------------------------------------|

| ·   | Natural gas gathering and processing segment operating income of $32.2 million, compared with $39.8 million in the first quarter 2009; |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------|

----

| ·   | Natural gas pipelines segment operating income of $44.9 million, compared with $32.6 million in the first quarter 2009; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------|

| ·   | Natural gas liquids segment operating income of $43.9 million, compared with $52.3 million in the first quarter 2009; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------|

| ·   | Equity earnings from investments of $21.1 million, compared with $21.2 million in the first quarter 2009; |
|--------------------|-----------------------------------------------------------------------------------------------------------|

| ·   | Announcing $405 million to $470 million in growth projects in the natural gas gathering and processing segment and the natural gas liquids segment, which includes the construction of a new 100 MMcf/d natural gas processing facility in the Bakken Shale in the Williston Basin in North Dakota - the Garden Creek plant; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | Signing a definitive 10-year, firm-space fractionation services agreement with Targa Resources Partners for 60,000 barrels per day of additional fractionation capacity at its Cedar Bayou fractionator in Mont Belvieu, Texas, which is scheduled to be operational in the second quarter of 2011; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | Capital expenditures of $35.8 million, compared with $192.5 million in the first quarter 2009; |
|--------------------|------------------------------------------------------------------------------------------------|

| ·   | Completing a public offering of approximately 5.5 million common units, generating net proceeds of approximately $322.7 million in February 2010; |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | Having $310 million outstanding and $558 million available under the partnership’s revolving credit facility at March 31, 2010; and |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | Increasing the quarterly cash distribution to $1.11 per unit, payable on May 14, 2010, to unitholders of record as of April 30, 2010. |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------|

----

|                                       |   | Three Months Ended |      |
|--------------------------------------------|--------|--------------------|-----------|
|                                       |   | March 31,          |      |
| Operating Information                      |   | 2010               |      |   | 2009 |   |
| Percent of proceeds                        |   |               |      |   |   |   |
|   Wellhead purchases (MMBtu/d)   |   |               | 44,586    |   |   |   | 60,496 |   |
|   NGL sales (Bbl/d)              |   |               | 5,014     |   |   |   | 5,040 |   |
|   Residue gas sales (MMBtu/d)    |   |               | 38,395    |   |   |   | 34,819 |   |
|   Condensate sales (Bbl/d)       |   |               | 1,918     |   |   |   | 2,095 |   |
|   Percentage of total net margin |   |               | 53%       |   |   |   | 50% |   |
| Fee-based                                  |   |               |      |   |   |   |   |   |
|   Wellhead volumes (MMBtu/d)     |   |               | 1,092,061 |   |   |   | 1,163,376 |   |
|   Average rate ($/MMBtu)         |   | $                  | 0.30      |   |   | $ | 0.28 |   |
|   Percentage of total net margin |   |               | 36%       |   |   |   | 35% |   |
| Keep-whole                                 |   |               |      |   |   |   |   |   |
|   NGL shrink (MMBtu/d)           |   |               | 13,819    |   |   |   | 16,960 |   |
|   Plant fuel (MMBtu/d)           |   |               | 1,714     |   |   |   | 2,182 |   |
|   Condensate shrink (MMBtu/d)    |   |               | 1,579     |   |   |   | 1,755 |   |
|   Condensate sales (Bbl/d)       |   |               | 320       |   |   |   | 355 |   |
|   Percentage of total net margin |   |               | 11%       |   |   |   | 15% |   |
|                                       |   |               |      |   |   |   |   |   |

|                                 |   | Nine Months Ending |   |
|--------------------------------------|--------|--------------------|--------|
|                                 |   | December 31, 2010  |   |
|                                 |   | Volumes Hedged     |   |  Average Price |   | Percentage Hedged |   |
| NGLs (Bbl/d) (a)                     |   |               | 5,261  |   |   | $ | 1.04 |   | / gallon |   |   | 68% |   |
| Condensate (Bbl/d) (a)               |   |               | 1,648  |   |   | $ | 1.81 |   | / gallon |   |   | 76% |   |
| Total (Bbl/d)                        |   |               | 6,909  |   |   | $ | 1.22 |   | / gallon |   |   | 70% |   |
| Natural gas (MMBtu/d)                |   |               | 26,504 |   |   | $ | 5.60 |   | / MMBtu |   |   | 81% |   |
| (a) - Hedged with fixed-price swaps. |   |               |   |   |   |   |   |   |   |   |   |   |   |

|                                 |   | Year Ending       |   |
|--------------------------------------|--------|-------------------|--------|
|                                 |   | December 31, 2011 |   |
|                                 |   | Volumes Hedged    |   |  Average Price |   | Percentage Hedged |   |
| NGLs (Bbl/d) (a)                     |   |              | 902    |   |   | $ | 1.34 |   | / gallon |   |   | 13% |   |
| Condensate (Bbl/d) (a)               |   |              | 596    |   |   | $ | 2.12 |   | / gallon |   |   | 26% |   |
| Total (Bbl/d)                        |   |              | 1,498  |   |   | $ | 1.65 |   | / gallon |   |   | 16% |   |
| Natural gas (MMBtu/d)                |   |              | 16,616 |   |   | $ | 6.29 |   | / MMBtu |   |   | 43% |   |
| (a) - Hedged with fixed-price swaps. |   |              |   |   |   |   |   |   |   |   |   |   |   |

----

----

| ·   | Construction of a new 100 million cubic feet per day (MMcf/d) natural gas processing facility, the Garden Creek plant, in eastern McKenzie County, N.D., and related expansions that are estimated to cost between $150 million and $210 million and will double the partnership’s natural gas processing capacity in the Williston Basin.  Completion is expected in the fourth quarter of 2011. |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | An additional $200 million to $205 million during 2010 and 2011 for new well connections, expansions and upgrades to its existing natural gas gathering system infrastructure in the Bakken Shale. |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | An additional $55 million investment in 2010 and 2011 in the Woodford Shale in Oklahoma, with projects in the natural gas gathering and processing and the natural gas liquids segments. |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

----

----

| ·   | the effects of weather and other natural phenomena on our operations, demand for our services and energy prices; |
|--------------------|------------------------------------------------------------------------------------------------------------------|

| ·   | competition from other United States and foreign energy suppliers and transporters, as well as alternative forms of energy, including, but not limited to, solar power, wind power, geothermal energy and biofuels such as ethanol and biodiesel; |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the capital intensive nature of our businesses; |
|--------------------|-------------------------------------------------|

| ·   | the profitability of assets or businesses acquired or constructed by us; |
|--------------------|--------------------------------------------------------------------------|

| ·   | our ability to make cost-saving changes in operations; |
|--------------------|--------------------------------------------------------|

| ·   | risks of marketing, trading and hedging activities, including the risks of changes in energy prices or the financial condition of our counterparties; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the uncertainty of estimates, including accruals and costs of environmental remediation; |
|--------------------|------------------------------------------------------------------------------------------|

| ·   | the timing and extent of changes in energy commodity prices; |
|--------------------|--------------------------------------------------------------|

----

| ·   | the effects of changes in governmental policies and regulatory actions, including changes with respect to income and other taxes, environmental compliance, climate change initiatives, authorized rates of recovery of gas and gas transportation costs; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the impact on drilling and production by factors beyond our control, including the demand for natural gas and crude oil; producers’ desire and ability to obtain necessary permits; reserve performance; and capacity constraints on the pipelines that transport crude oil, natural gas and NGLs from producing areas and our facilities; |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | difficulties or delays experienced by trucks or pipelines in delivering products to or from our terminals or pipelines; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------|

| ·   | changes in demand for the use of natural gas because of market conditions caused by concerns about global warming; |
|--------------------|--------------------------------------------------------------------------------------------------------------------|

| ·   | conflicts of interest between us, our general partner, ONEOK Partners GP, and related parties of ONEOK Partners GP; |
|--------------------|---------------------------------------------------------------------------------------------------------------------|

| ·   | the impact of unforeseen changes in interest rates, equity markets, inflation rates, economic recession and other external factors over which we have no control; |
|--------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | our indebtedness could make us vulnerable to general adverse economic and industry conditions, limit our ability to borrow additional funds and/or place us at competitive disadvantages compared with our competitors that have less debt or have other adverse consequences; |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | actions by rating agencies concerning the credit ratings of us or our general partner; |
|--------------------|----------------------------------------------------------------------------------------|

| ·   | the results of administrative proceedings and litigation, regulatory actions and receipt of expected clearances involving the Oklahoma Corporation Commission (OCC), Kansas Corporation Commission (KCC), Texas regulatory authorities or any other local, state or federal regulatory body, including the Federal Energy Regulatory Commission (FERC); |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | our ability to access capital at competitive rates or on terms acceptable to us; |
|--------------------|----------------------------------------------------------------------------------|

| ·   | risks associated with adequate supply to our gathering, processing, fractionation and pipeline facilities, including production declines that outpace new drilling; |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the risk that material weaknesses or significant deficiencies in our internal control over financial reporting could emerge or that minor problems could become significant; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the impact and outcome of pending and future litigation; |
|--------------------|----------------------------------------------------------|

| ·   | the ability to market pipeline capacity on favorable terms, including the effects of: |
|--------------------|---------------------------------------------------------------------------------------|

| -   | future demand for and prices of natural gas and NGLs; |
|---------------|-------------------------------------------------------|

| -   | competitive conditions in the overall energy market; |
|---------------|------------------------------------------------------|

| -   | availability of supplies of Canadian and United States natural gas; and |
|---------------|-------------------------------------------------------------------------|

| -   | availability of additional storage capacity; |
|---------------|----------------------------------------------|

| ·   | performance of contractual obligations by our customers, service providers, contractors and shippers; |
|--------------------|-------------------------------------------------------------------------------------------------------|

| ·   | the timely receipt of approval by applicable governmental entities for construction and operation of our pipeline and other projects and required regulatory clearances; |
|--------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | our ability to acquire all necessary permits, consents and other approvals in a timely manner, to promptly obtain all necessary materials and supplies required for construction, and to construct gathering, processing, storage, fractionation and transportation facilities without labor or contractor problems; |
|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the mechanical integrity of facilities operated; |
|--------------------|--------------------------------------------------|

| ·   | demand for our services in the proximity of our facilities; |
|--------------------|-------------------------------------------------------------|

| ·   | our ability to control operating costs; |
|--------------------|-----------------------------------------|

| ·   | acts of nature, sabotage, terrorism or other similar acts that cause damage to our facilities or our suppliers’ or shippers’ facilities; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | economic climate and growth in the geographic areas in which we do business; |
|--------------------|------------------------------------------------------------------------------|

| ·   | the risk of a prolonged slowdown in growth or decline in the U.S. economy or the risk of delay in growth recovery in the U.S. economy, including liquidity risks in U.S. credit markets; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the impact of recently issued and future accounting updates and other changes in accounting policies; |
|--------------------|-------------------------------------------------------------------------------------------------------|

| ·   | the possibility of future terrorist attacks or the possibility or occurrence of an outbreak of, or changes in, hostilities or changes in the political conditions in the Middle East and elsewhere; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the risk of increased costs for insurance premiums, security or other items as a consequence of terrorist attacks; |
|--------------------|--------------------------------------------------------------------------------------------------------------------|

| ·   | risks associated with pending or possible acquisitions and dispositions, including our ability to finance or integrate any such acquisitions and any regulatory delay or conditions imposed by regulatory bodies in connection with any such acquisitions and dispositions; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

----

| ·   | the impact of unsold pipeline capacity being greater or less than expected; |
|--------------------|-----------------------------------------------------------------------------|

| ·   | the ability to recover operating costs and amounts equivalent to income taxes, costs of property, plant and equipment and regulatory assets in our state and FERC-regulated rates; |
|--------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | the composition and quality of the natural gas and NGLs we gather and process in our plants and transport on our pipelines; |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------|

| ·   | the efficiency of our plants in processing natural gas and extracting and fractionating NGLs; |
|--------------------|-----------------------------------------------------------------------------------------------|

| ·   | the impact of potential impairment charges; |
|--------------------|---------------------------------------------|

| ·   | the risk inherent in the use of information systems in our respective businesses, implementation of new software and hardware, and the impact on the timeliness of information for financial reporting; |
|--------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| ·   | our ability to control construction costs and completion schedules of our pipelines and other projects; and |
|--------------------|-------------------------------------------------------------------------------------------------------------|

| ·   | the risk factors listed in the reports we have filed and may file with the Securities and Exchange Commission (SEC), which are incorporated by reference. |
|--------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|

----

| ONEOK Partners, L.P. and Subsidiaries                     |   |                                            |      |   |   |   |
|-----------------------------------------------------------|--------|-------------------------------------------------|-----------|--------|--------|--------|
| CONSOLIDATED STATEMENTS OF INCOME                         |   |                                            |      |   |   |   |
|                                                      |   | Three Months Ended                              |      |
|                                                      |   | March 31,                                       |      |
| (Unaudited)                                               |   | 2010                                            |      |   | 2009   |   |
|                                                      |   | (Thousands of dollars, except per unit amounts) |      |
|                                                      |   |                                            |      |   |   |   |
| Revenues                                                  |   | $                                               | 2,204,006 |   |   | $      | 1,250,865 |   |
| Cost of sales and fuel                                    |   |                                            | 1,942,881 |   |   |   | 997,324 |   |
| Net margin                                                |   |                                            | 261,125   |   |   |   | 253,541 |   |
| Operating expenses                                        |   |                                            |      |   |   |   |   |   |
| Operations and maintenance                                |   |                                            | 87,205    |   |   |   | 77,679 |   |
| Depreciation and amortization                             |   |                                            | 43,871    |   |   |   | 39,940 |   |
| General taxes                                             |   |                                            | 9,101     |   |   |   | 11,767 |   |
| Total operating expenses                                  |   |                                            | 140,177   |   |   |   | 129,386 |   |
| Gain (loss) on sale of assets                             |   |                                            | (786      | )      |   |   | 664 |   |
| Operating income                                          |   |                                            | 120,162   |   |   |   | 124,819 |   |
| Equity earnings from investments                          |   |                                            | 21,116    |   |   |   | 21,222 |   |
| Allowance for equity funds used during construction       |   |                                            | 247       |   |   |   | 9,003 |   |
| Other income                                              |   |                                            | 1,850     |   |   |   | 391 |   |
| Other expense                                             |   |                                            | (342      | )      |   |   | (2,046 | ) |
| Interest expense                                          |   |                                            | (54,153   | )      |   |   | (50,908 | ) |
| Income before income taxes                                |   |                                            | 88,880    |   |   |   | 102,481 |   |
| Income taxes                                              |   |                                            | (4,860    | )      |   |   | (2,871 | ) |
| Net income                                                |   |                                            | 84,020    |   |   |   | 99,610 |   |
| Less: Net income attributable to noncontrolling interests |   |                                            | 152       |   |   |   | 19 |   |
| Net income attributable to ONEOK Partners, L.P.           |   | $                                               | 83,868    |   |   | $      | 99,591 |   |
|                                                      |   |                                            |      |   |   |   |   |   |
| Limited partners' interest in net income:                 |   |                                            |      |   |   |   |   |   |
| Net income attributable to ONEOK Partners, L.P.           |   | $                                               | 83,868    |   |   | $      | 99,591 |   |
| General partner's interest in net income                  |   |                                            | (27,387   | )      |   |   | (22,312 | ) |
| Limited partners' interest in net income                  |   | $                                               | 56,481    |   |   | $      | 77,279 |   |
|                                                      |   |                                            |      |   |   |   |   |   |
| Limited partners' net income per unit, basic and diluted  |   | $                                               | 0.57      |   |   | $      | 0.85 |   |
|                                                      |   |                                            |      |   |   |   |   |   |
| Number of units used in computation (thousands)           |   |                                            | 99,721    |   |   |   | 90,920 |   |

----

| ONEOK Partners, L.P. and Subsidiaries                                                                                                       |   |                   |      |   |         |   |
|---------------------------------------------------------------------------------------------------------------------------------------------|--------|------------------------|-----------|--------|--------------|--------|
| CONSOLIDATED BALANCE SHEETS                                                                                                                 |   |                   |      |   |         |   |
|                                                                                                                                        |   | March 31,              |      |   | December 31, |   |
| (Unaudited)                                                                                                                                 |   | 2010                   |      |   | 2009         |   |
| Assets                                                                                                                                      |   | (Thousands of dollars) |      |
| Current assets                                                                                                                              |   |                   |      |   |         |   |
| Cash and cash equivalents                                                                                                                   |   | $                      | 5,379     |   |         | $      | 3,151 |   |
| Accounts receivable, net                                                                                                                    |   |                   | 451,811   |   |         |   | 624,635 |   |
| Affiliate receivables                                                                                                                       |   |                   | 33,935    |   |         |   | 32,397 |   |
| Gas and natural gas liquids in storage                                                                                                      |   |                   | 219,349   |   |         |   | 217,585 |   |
| Commodity imbalances                                                                                                                        |   |                   | 98,011    |   |         |   | 188,177 |   |
| Other current assets                                                                                                                        |   |                   | 44,802    |   |         |   | 36,148 |   |
| Total current assets                                                                                                                        |   |                   | 853,287   |   |         |   | 1,102,093 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Property, plant and equipment                                                                                                               |   |                   |      |   |         |   |   |   |
| Property, plant and equipment                                                                                                               |   |                   | 6,385,176 |   |         |   | 6,353,909 |   |
| Accumulated depreciation and amortization                                                                                                   |   |                   | 1,011,304 |   |         |   | 972,497 |   |
| Net property, plant and equipment                                                                                                           |   |                   | 5,373,872 |   |         |   | 5,381,412 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Investments and other assets                                                                                                                |   |                   |      |   |         |   |   |   |
| Investments in unconsolidated affiliates                                                                                                    |   |                   | 762,435   |   |         |   | 765,163 |   |
| Goodwill and intangible assets                                                                                                              |   |                   | 666,953   |   |         |   | 668,870 |   |
| Other assets                                                                                                                                |   |                   | 40,822    |   |         |   | 35,721 |   |
| Total investments and other assets                                                                                                          |   |                   | 1,470,210 |   |         |   | 1,469,754 |   |
| Total assets                                                                                                                                |   | $                      | 7,697,369 |   |         | $      | 7,953,259 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Liabilities and partners' equity                                                                                                            |   |                   |      |   |         |   |   |   |
| Current liabilities                                                                                                                         |   |                   |      |   |         |   |   |   |
| Current maturities of long-term debt                                                                                                        |   | $                      | 486,931   |   |         | $      | 261,931 |   |
| Notes payable                                                                                                                               |   |                   | 310,000   |   |         |   | 523,000 |   |
| Accounts payable                                                                                                                            |   |                   | 519,675   |   |         |   | 694,290 |   |
| Affiliate payables                                                                                                                          |   |                   | 16,983    |   |         |   | 21,866 |   |
| Commodity imbalances                                                                                                                        |   |                   | 245,964   |   |         |   | 392,688 |   |
| Other current liabilities                                                                                                                   |   |                   | 124,732   |   |         |   | 153,539 |   |
| Total current liabilities                                                                                                                   |   |                   | 1,704,285 |   |         |   | 2,047,314 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Long-term debt, excluding current maturities                                                                                                |   |                   | 2,593,157 |   |         |   | 2,822,086 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Deferred credits and other liabilities                                                                                                      |   |                   | 79,404    |   |         |   | 73,798 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Commitments and contingencies                                                                                                               |   |                   |      |   |         |   |   |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Partners' equity                                                                                                                            |   |                   |      |   |         |   |   |   |
| ONEOK Partners, L.P. partners’ equity:                                                                                                |   |                   |      |   |         |   |   |   |
| General partner                                                                                                                             |   |                   | 92,602    |   |         |   | 84,434 |   |
| Common units: 65,413,677 and 59,912,777 units issued and outstanding at   March 31, 2010 and December 31, 2009, respectively |   |                   | 1,854,011 |   |         |   | 1,561,762 |   |
| Class B units: 36,494,126 units issued and outstanding at   March 31, 2010 and December 31, 2009                             |   |                   | 1,361,205 |   |         |   | 1,380,299 |   |
| Accumulated other comprehensive income (loss)                                                                                               |   |                   | 7,318     |   |         |   | (22,037 | ) |
| Total ONEOK Partners, L.P. partners' equity                                                                                                 |   |                   | 3,315,136 |   |         |   | 3,004,458 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Noncontrolling interests in consolidated subsidiaries                                                                                       |   |                   | 5,387     |   |         |   | 5,603 |   |
|                                                                                                                                        |   |                   |      |   |         |   |   |   |
| Total partners' equity                                                                                                                      |   |                   | 3,320,523 |   |         |   | 3,010,061 |   |
| Total liabilities and partners' equity                                                                                                      |   | $                      | 7,697,369 |   |         | $      | 7,953,259 |   |

----

| ONEOK Partners, L.P. and Subsidiaries                                           |   |                   |     |   |   |   |
|---------------------------------------------------------------------------------|--------|------------------------|----------|--------|--------|--------|
| CONSOLIDATED STATEMENTS OF CASH FLOWS                                           |   | Three Months Ended     |     |
|                                                                            |   | March 31,              |     |
| (Unaudited)                                                                     |   | 2010                   |     |   | 2009   |   |
|                                                                            |   | (Thousands of dollars) |     |
| Operating activities                                                            |   |                   |     |   |   |   |
| Net income                                                                      |   | $                      | 84,020   |   |   | $      | 99,610 |   |
| Depreciation and amortization                                                   |   |                   | 43,871   |   |   |   | 39,940 |   |
| Allowance for equity funds used during construction                             |   |                   | (247     | )      |   |   | (9,003 | ) |
| Loss (gain) on sale of assets                                                   |   |                   | 786      |   |   |   | (664 | ) |
| Deferred income taxes                                                           |   |                   | 1,239    |   |   |   | 1,706 |   |
| Equity earnings from investments                                                |   |                   | (21,116  | )      |   |   | (21,222 | ) |
| Distributions received from unconsolidated affiliates                           |   |                   | 21,998   |   |   |   | 25,187 |   |
| Changes in assets and liabilities:                                              |   |                   |     |   |   |   |   |   |
| Accounts receivable                                                             |   |                   | 172,824  |   |   |   | 11,224 |   |
| Affiliate receivables                                                           |   |                   | (1,538   | )      |   |   | 4,880 |   |
| Gas and natural gas liquids in storage                                          |   |                   | (1,764   | )      |   |   | 44,641 |   |
| Accounts payable                                                                |   |                   | (168,406 | )      |   |   | (65,065 | ) |
| Affiliate payables                                                              |   |                   | (4,883   | )      |   |   | (4,961 | ) |
| Commodity imbalances, net                                                       |   |                   | (56,558  | )      |   |   | (59,078 | ) |
| Accrued interest                                                                |   |                   | 23,045   |   |   |   | 33,555 |   |
| Other assets and liabilities                                                    |   |                   | (37,792  | )      |   |   | (25,974 | ) |
| Cash provided by operating activities                                           |   |                   | 55,479   |   |   |   | 74,776 |   |
|                                                                            |   |                   |     |   |   |   |   |   |
| Investing activities                                                            |   |                   |     |   |   |   |   |   |
| Changes in investments in unconsolidated affiliates                             |   |                   | 1,334    |   |   |   | 3,362 |   |
| Capital expenditures (less allowance for equity funds used during construction) |   |                   | (35,827  | )      |   |   | (192,494 | ) |
| Proceeds from sale of assets                                                    |   |                   | 138      |   |   |   | 1,083 |   |
| Cash used in investing activities                                               |   |                   | (34,355  | )      |   |   | (188,049 | ) |
|                                                                            |   |                   |     |   |   |   |   |   |
| Financing activities                                                            |   |                   |     |   |   |   |   |   |
| Cash distributions:                                                             |   |                   |     |   |   |   |   |   |
| General and limited partners                                                    |   |                   | (132,086 | )      |   |   | (120,932 | ) |
| Noncontrolling interests                                                        |   |                   | (368     | )      |   |   | (343 | ) |
| Borrowing (repayment) of notes payable, net                                     |   |                   | (213,000 | )      |   |   | 36,700 |   |
| Repayment of notes payable with maturities over 90 days                         |   |                   | -        |   |   |   | (470,000 | ) |
| Issuance of long-term debt, net of discounts                                    |   |                   | -        |   |   |   | 498,325 |   |
| Long-term debt financing costs                                                  |   |                   | -        |   |   |   | (4,000 | ) |
| Repayment of long-term debt                                                     |   |                   | (2,983   | )      |   |   | (2,983 | ) |
| Issuance of common units, net of discounts                                      |   |                   | 322,721  |   |   |   | - |   |
| Contribution from general partner                                               |   |                   | 6,820    |   |   |   | - |   |
| Cash used in financing activities                                               |   |                   | (18,896  | )      |   |   | (63,233 | ) |
| Change in cash and cash equivalents                                             |   |                   | 2,228    |   |   |   | (176,506 | ) |
| Cash and cash equivalents at beginning of period                                |   |                   | 3,151    |   |   |   | 177,635 |   |
| Cash and cash equivalents at end of period                                      |   | $                      | 5,379    |   |   | $      | 1,129 |   |

----

| ONEOK Partners, L.P. and Subsidiaries                                     |   |                                   |   |   |   |   |
|---------------------------------------------------------------------------|--------|----------------------------------------|--------|--------|--------|--------|
| INFORMATION AT A GLANCE                                                   |   |                                   |   |   |   |   |
|                                                                      |   |                                   |   |   |   |   |
|                                                                      |   | Three Months Ended                     |   |
|                                                                      |   | March 31,                              |   |
| (Unaudited)                                                               |   | 2010                                   |   |   | 2009   |   |
|                                                                      |   | (Millions of dollars, except as noted) |   |
| Natural Gas Gathering and Processing                                      |   |                                   |   |   |   |   |
| Net margin                                                                |   | $                                      | 81.3   |   |   | $      | 86.1 |   |
| Operating costs                                                           |   | $                                      | 34.4   |   |   | $      | 31.8 |   |
| Depreciation and amortization                                             |   | $                                      | 14.7   |   |   | $      | 14.5 |   |
| Operating income                                                          |   | $                                      | 32.2   |   |   | $      | 39.8 |   |
| Equity earnings from investments                                          |   | $                                      | 5.7    |   |   | $      | 4.5 |   |
| Natural gas gathered (BBtu/d)                                             |   |                                   | 1,092  |   |   |   | 1,163 |   |
| Natural gas processed (BBtu/d)                                            |   |                                   | 664    |   |   |   | 653 |   |
| NGL sales (MBbl/d)                                                        |   |                                   | 43     |   |   |   | 41 |   |
| Residue gas sales (BBtu/d)                                                |   |                                   | 275    |   |   |   | 285 |   |
| *Realized composite NGL net sales price ($/gallon)                        |   | $                                      | 0.99   |   |   | $      | 0.88 |   |
| *Realized condensate net sales price ($/Bbl)                              |   | $                                      | 62.39  |   |   | $      | 68.45 |   |
| *Realized residue gas net sales price ($/MMBtu)                           |   | $                                      | 5.20   |   |   | $      | 3.58 |   |
| Realized gross processing spread ($/MMBtu) (a)                            |   | $                                      | 6.37   |   |   | $      | 7.43 |   |
| Capital expenditures - growth                                             |   | $                                      | 15.5   |   |   | $      | 25.5 |   |
| Capital expenditures - maintenance                                        |   | $                                      | 3.6    |   |   | $      | 3.3 |   |
| (a) - Includes volumes for consolidated entities only.                    |   |                                   |   |   |   |   |   |   |
| * Includes equity volumes only.                                           |   |                                   |   |   |   |   |   |   |
|                                                                      |   |                                   |   |   |   |   |   |   |
| Natural Gas Pipelines                                                     |   |                                   |   |   |   |   |   |   |
| Net margin                                                                |   | $                                      | 78.6   |   |   | $      | 65.6 |   |
| Operating costs                                                           |   | $                                      | 22.8   |   |   | $      | 20.2 |   |
| Depreciation and amortization                                             |   | $                                      | 10.9   |   |   | $      | 12.8 |   |
| Operating income                                                          |   | $                                      | 44.9   |   |   | $      | 32.6 |   |
| Equity earnings from investments                                          |   | $                                      | 15.1   |   |   | $      | 16.2 |   |
| Natural gas transportation capacity contracted (MMcf/d)                   |   |                                   | 5,860  |   |   |   | 5,247 |   |
| Transportation capacity subscribed                                        |   |                                   | 91%    |   |   |   | 79% |   |
| Average natural gas price   Mid-Continent region ($/MMBtu) |   | $                                      | 5.03   |   |   | $      | 3.19 |   |
| Capital expenditures - growth                                             |   | $                                      | 2.0    |   |   | $      | 17.2 |   |
| Capital expenditures - maintenance                                        |   | $                                      | 1.2    |   |   | $      | 0.2 |   |
|                                                                      |   |                                   |   |   |   |   |   |   |
| Natural Gas Liquids                                                       |   |                                   |   |   |   |   |   |   |
| Net margin                                                                |   | $                                      | 104.0  |   |   | $      | 102.6 |   |
| Operating costs                                                           |   | $                                      | 41.0   |   |   | $      | 37.6 |   |
| Depreciation and amortization                                             |   | $                                      | 18.3   |   |   | $      | 12.7 |   |
| Operating income                                                          |   | $                                      | 43.9   |   |   | $      | 52.3 |   |
| Equity earnings from investments                                          |   | $                                      | 0.4    |   |   | $      | 0.5 |   |
| NGL sales (MBbl/d)                                                        |   |                                   | 427    |   |   |   | 380 |   |
| NGLs fractionated (MBbl/d)                                                |   |                                   | 492    |   |   |   | 465 |   |
| NGLs transported-gathering lines (MBbl/d)                                 |   |                                   | 441    |   |   |   | 324 |   |
| NGLs transported-distribution lines (MBbl/d)                              |   |                                   | 467    |   |   |   | 445 |   |
| Conway-to-Mont Belvieu OPIS average price differential                    |   |                                   |   |   |   |   |   |   |
|   Ethane ($/gallon)                                             |   | $                                      | 0.08   |   |   | $      | 0.08 |   |
| Capital expenditures - growth                                             |   | $                                      | 11.6   |   |   | $      | 140.9 |   |
| Capital expenditures - maintenance                                        |   | $                                      | 4.2    |   |   | $      | 5.3 |   |

----

| ONEOK Partners, L.P. and Subsidiaries                              |   |                                            |    |   |   |   |
|--------------------------------------------------------------------|--------|-------------------------------------------------|---------|--------|--------|--------|
| RECONCILIATION OF NON-GAAP FINANCIAL MEASURES                      |   |                                            |    |   |   |   |
|                                                               |   |                                            |    |   |   |   |
|                                                               |   | Three Months Ended                              |    |
|                                                               |   | March 31,                                       |    |
| (Unaudited)                                                        |   | 2010                                            |    |   | 2009   |   |
|                                                               |   | (Thousands of dollars, except per unit amounts) |
|                                                               |   |                                            |    |   |   |   |
| Reconciliation of Net Income to EBITDA and Distributable Cash Flow |   |                                            |    |   |
| Net income                                                         |   | $                                               | 84,020  |   |   | $      | 99,610 |   |
| Interest expense                                                   |   |                                            | 54,153  |   |   |   | 50,908 |   |
| Depreciation and amortization                                      |   |                                            | 43,871  |   |   |   | 39,940 |   |
| Income taxes                                                       |   |                                            | 4,860   |   |   |   | 2,871 |   |
| Allowance for equity funds used during construction                |   |                                            | (247    | )      |   |   | (9,003 | ) |
| EBITDA                                                             |   |                                            | 186,657 |   |   |   | 184,326 |   |
| Interest expense                                                   |   |                                            | (54,153 | )      |   |   | (50,908 | ) |
| Maintenance capital                                                |   |                                            | (9,386  | )      |   |   | (8,782 | ) |
| Equity earnings from investments                                   |   |                                            | (21,116 | )      |   |   | (21,222 | ) |
| Distributions received from unconsolidated affiliates              |   |                                            | 23,529  |   |   |   | 33,331 |   |
| Other                                                              |   |                                            | (3,203  | )      |   |   | (2,172 | ) |
| Distributable cash flow                                            |   | $                                               | 122,328 |   |   | $      | 134,573 |   |
|                                                               |   |                                            |    |   |   |   |   |   |
|                                                               |   |                                            |    |   |   |   |   |   |
| Distributions to general partner                                   |   |                                            | (28,544 | )      |   |   | (22,738 | ) |
| Distributable cash flow to limited partners                        |   | $                                               | 93,784  |   |   | $      | 111,835 |   |
|                                                               |   |                                            |    |   |   |   |   |   |
| Distributions declared per limited partner unit                    |   | $                                               | 1.11    |   |   | $      | 1.08 |   |
| Coverage ratio                                                     |   |                                            | 0.85    |   |   |   | 1.14 |   |
|                                                               |   |                                            |    |   |   |   |   |   |
|                                                               |   |                                            |    |   |   |   |   |   |
| Number of units used in computation (thousands)                    |   |                                            | 99,721  |   |   |   | 90,920 |   |