Exhibit 12.1

ONEOK Partners, L.P.

Computation of Ratio of Earnings to Fixed Charges



|                                                                            |  |                                  |         |   |      |   |         |      |  |   |         |   |  |      |         |   |  |   |         |  
|--------------------------------------------------------------------------- |  | -------------------------------- | ------- | - | ---- | - | ------- | ---- |  | - | ------- | - |  | ---- | ------- | - |  | - | ------- | -
|                                                                            |  | Twelve months ended December 31, |        
|(Unaudited)                                                                 |  | 2003                             |         |   | 2004 |   |         | 2005 |  |   | 2006    |   |  | 2007 |        
|                                                                            |  | (Thousands of dollars)           |        
|Fixed Charges, as defined                                                   |  |                                  |         |   |      |   |         |      |  |   |         |   |  |      |         |   |  |   |         |  
|Interest on long-term debt                                                  |  | $                                | 80,653  |   |      | $ | 79,020  |      |  | $ | 90,066  |   |  | $    | 136,533 |   |  | $ | 146,046 |  
|Other interest                                                              |  |                                  | 45      |   |      |   | 15      |      |  |   | 3       |   |  |      | 439     |   |  |   | 4,714   |  
|Amortization of debt discount, premium & expense                            |  |                                  | (1,539  | ) |      |   | (1,690  | )    |  |   | (2,379  | ) |  |      | (2,294  | ) |  |   | 1,765   |  
|Interest on lease agreements                                                |  |                                  | 1,210   |   |      |   | 1,192   |      |  |   | 1,522   |   |  |      | 5,605   |   |  |   | 6,392   |  
|                                                                            |  |                                  |         |   |      |   |         |      |  |   |         |   |  |      |         |   |  |   |         |  
|Total Fixed Charges                                                         |  |                                  | 80,369  |   |      |   | 78,537  |      |  |   | 89,212  |   |  |      | 140,283 |   |  |   | 158,917 |  
|                                                                            |  |                                  |         |   |      |   |         |      |  |   |         |   |  |      |         |   |  |   |         |  
|Earnings before income taxes and undistributed income from equity investees |  |                                  | (49,244 | ) |      |   | 190,245 |      |  |   | 189,042 |   |  |      | 501,595 |   |  |   | 417,305 |  
|                                                                            |  |                                  |         |   |      |   |         |      |  |   |         |   |  |      |         |   |  |   |         |  
|Earnings available for fixed charges                                        |  | $                                | 31,125  |   |      | $ | 268,782 |      |  | $ | 278,254 |   |  | $    | 641,878 |   |  | $ | 576,222 |  
|                                                                            |  |                                  |         |   |      |   |         |      |  |   |         |   |  |      |         |   |  |   |         |  
|Ratio of earnings to fixed charges                                          |  |                                  | 0.39    | x |      |   | 3.42    | x    |  |   | 3.12    | x |  |      | 4.58    | x |  |   | 3.63    | x
|                                                                            |  |                                  |         |   |      |   |         |      |  |   |         |   |  |      |         |   |  |   |         |  

For purposes of computing the ratio of earnings to combined fixed charges and preferred stock dividend
requirements, earnings consists of income before cumulative effect of a change in accounting principle plus fixed charges, minority interest, income taxes and distributed income of equity method investees, less capitalized interest and
undistributed income for equity investees. Fixed charges consists of interest expensed and capitalized, the amortization of debt discounts and issue costs and the representative interest portion of operating leases.