UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWashington, D.C.20549



FORM 40-F



[Check one]



| |  ̈ | REGISTRATION STATEMENT PURSUANT TO SECTION 12 OF        | 
| | - | ------------------------------------------------------- | 
| |   | THE
    SECURITIES EXCHANGE ACT OF 1934                 | 
| |   | OR                                                      | 
| | ý | ANNUAL
    REPORT PURSUANT TO SECTION 13(a) OR 15(d) OF | 
| |   | THE
    SECURITIES EXCHANGE ACT OF 1934                 | 



|For the fiscal year ended | December 31, 2011 | Commission File Number | 000-30514
|------------------------- | ----------------- | ---------------------- | ---------
|                          |                   |                        |          



|ARC RESOURCES LTD.                                    
|------------------------------------------------------
|(Exact name of Registrant as specified in its charter)



|N/A                                                                                                     
|--------------------------------------------------------------------------------------------------------
|(Translation of Registrant's name into English (if applicable))                                         
|                                                                                                        
|ALBERTA                                                                                                 
|(Province or other jurisdiction of incorporation or organization)                                       
|                                                                                                        
|1311                                                                                                    
|(Primary Standard Industrial Classification Code Number (if applicable))                                
|                                                                                                        
|N/A                                                                                                     
|(I.R.S. Employer Identification Number (if applicable))                                                 
|                                                                                                        
|1200, 308 4th Avenue S.W., Calgary, Alberta, Canada T2P 0H7 (403) 503-8600                              
|(Address and telephone number of Registrant's principal executive offices)                              
|                                                                                                        
|Corporation Service Company, 2711 Centerville Road, Suite 400, Wilmington, Delaware 19805 (302) 636-5401
|(Name, address (including zip code) and telephone number (including area code)                          
|of agent for service in the United States)                                                              



Securities registered or to be registered pursuant to Section 12(b) of the Act.



|Title of each class |     | Name of each exchange on which registered
|------------------- | --- | -----------------------------------------
|N/A                 | N/A



Securities registered or to be registered pursuant to Section 12(g) of the Act.



|COMMON SHARES   
|----------------
|(Title of Class)



Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act.



|N/A                 
|--------------------
|(Title
    of Class)















For annual reports, indicate by check mark
the information filed with this Form:



ý    Annual
information form          ý    Audited
annual financial statements



Indicate the number of outstanding shares
of each of the issuer's classes of capital or common stock as of the close of the period covered by the annual report.



288,895,582 Common Shares as at December 31,
2011



Indicate by check mark whether the Registrant
(1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange Act during the preceding 12 months (or for
such shorter period that the Registrant was required to file such reports) and (2) has been subject to such filing requirements
for the past 90 days.



ý
Yes            ̈ No



Indicate by check mark whether the registrant
has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted
and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter
period that the Registrant was required to submit and post such files).



 ̈
Yes          o No















Principal Documents



The following documents have been filed
as part of this Annual Report on Form 40-F:



| | A. | Annual Information Form
| | -- | -----------------------



For our Annual Information Form for the
fiscal year ended December 31, 2011, see Exhibit 99.1 of this Annual Report on Form 40-F.



| | B. | Audited Annual Financial Statements
| | -- | -----------------------------------



For our Consolidated Financial Statements
for the fiscal year ended December 31, 2011, including the report of Independent Registered Chartered Accountants with respect
thereto, see Exhibit 99.2 of this Annual Report on Form 40-F.



| | C. | Management's Discussion and Analysis
| | -- | ------------------------------------



For Management's Discussion and Analysis
for the fiscal year ended December 31, 2011, see Exhibit 99.3 of this Annual Report on Form 40-F.



| | Disclosure | Regarding Controls and Procedures.
| | ---------- | ----------------------------------



| | (a) | Certifications. See Exhibits 99.4, 99.5, 99.6 and
99.7 to this Annual Report on Form 40-F.
| | --- | ------------------------------------------------------------------------------------------



| | (b) | Disclosure
Controls and Procedures. As of the end of the Registrant’s fiscal year ended December 31, 2011, an evaluation of the
effectiveness of the Registrant’s "disclosure controls and procedures" (as such term is defined in Rules 13a-15(e)
and 15d-15(e) of the Securities Exchange Act of 1934, as amended (the "Exchange Act")) was carried out by the Registrant’s
management with the participation of the principal executive officer and principal financial officer. Based upon that evaluation,
the Registrant’s principal executive officer and principal financial officer have concluded that as of the end of that fiscal
year, the Registrant’s disclosure controls and procedures are effective to ensure that information required to be disclosed
by the Registrant in reports that it files or submits under the Exchange Act is (i) recorded, processed, summarized and reported
within the time periods specified in Securities and Exchange Commission rules and forms and (ii) accumulated and communicated
to the Registrant’s management, including its principal executive officer and principal financial officer, to allow timely
decisions regarding required disclosure.
| | --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



It should be noted that while
the Registrant’s principal executive officer and principal financial officer conclude that the Registrant’s disclosure
controls and procedures provide a reasonable level of assurance that they are effective, they do not expect that the Registrant’s
disclosure controls and procedures or internal control over financial reporting will prevent all errors and fraud. A control system,
no matter how well conceived or operated, can provide only reasonable, not absolute, assurance that the objectives of the control
system are met.



| | (c) | Management’s Annual Report on Internal Control Over
Financial Reporting. The required disclosure is included in the "Management Report" that accompanies the Registrant’s
Consolidated Financial Statements for the fiscal year ended December 31, 2011, filed as Exhibit 99.2 of this Annual Report on
Form 40-F.
| | --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| | (d) | (Attestation Report of the Registered Public Accounting
Firm. The required disclosure is included in the "Report of Independent Registered Chartered Accountants" that accompanies
the Registrant’s Consolidated Financial Statements for the fiscal year ended December 31, 2011, filed as Exhibit 99.2 of
this Annual Report on Form 40-F.
| | --- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------













| | (e) | Changes
in Internal Control Over Financial Reporting. During the fiscal year ended December 31, 2011, there were no changes in the
Registrant’s internal control over financial reporting that have materially affected, or are reasonably likely to materially
affect, the registrant’s internal control over financial reporting.
| | --- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



Notices Pursuant to Regulation
BTR



None.



Audit Committee Financial Expert



The Board of Directors (the "Board")
of the Registrant has determined that Mr. Fred Dyment and Ms. Kathleen O'Neill are audit committee financial experts (as defined
in paragraph 8(b) of General Instruction B to Form 40-F) currently serving on the Registrant's audit committee. Mr. Dyment
and Ms. O'Neill are independent members of the Board under the New York Stock Exchange Rule 303A.00 (Corporate Governance Standards).



Code of Ethics



The Registrant has adopted a code of ethics
(as that term is defined in paragraph 9(b) of General Instruction B to Form 40-F) that applies to its principal executive officer,
principal financial officer, principal accounting officer or controller, and persons performing similar functions and Senior Vice-President,
Capital Markets, its directors and all other employees of the Registrant. The code of ethics has been posted on the Registrant's
website at www.arcresources.com. Since the adoption of the code of ethics in 2004, there have not been any amendments to the code
of ethics (except for administrative amendments to co-ordinate the code of ethics with the Registrant's whistleblower policy, to
reflect that the Registrant is the successor to ARC Energy Trust and to include language concerning the ownership, protection
and proper use of the Registrant's assets and the use of social media sites for discussion of matters relating to the Registrant),
or waivers, including implicit waivers, from any provision of the code of ethics. The Registrant will post on its website any amendment
to, or waiver of, a provision of its code of ethics which requires disclosure within five business days following the date of any
such amendment or waiver.



Principal Accountant Fees and Services



The required disclosure is included under
the heading "Audit Committee Disclosures – Principal Accountant Fees and Services" in the Registrant's Annual Information
Form for the fiscal year ended December 31, 2011, filed as Exhibit 99.1 of this Annual Report on Form 40-F.



Off-Balance Sheet Arrangements



The Registrant has no off-balance sheet
arrangements that have or are reasonably likely to have a current or future effect on the Registrant's financial condition, changes
in financial condition, revenues or expenses, results of operations, liquidity, capital expenditures or capital resources that
is material to investors. For a discussion of the Registrant's other off-balance sheet arrangements, see page 23 of the Registrant's
Management's Discussion and Analysis for the fiscal year ended December 31, 2011, which is filed as Exhibit 99.3 to this Annual
Report on Form 40-F.













Tabular Disclosure of Contractual Obligations



Following is a summary of the Registrant's
contractual obligations and commitments as at December 31, 2011:



|                                            |  | Payments Due by Period |      
|------------------------------------------- |  | ---------------------- | -----
|(Cdn $ millions)                            |  | Less than 1 year       |      
|Debt repayments(1)                          |  |                        | 44.4 
|Interest payments(2)                        |  |                        | 24.7 
|Reclamation fund contributions(3)           |  |                        | 4.3  
|Purchase commitments                        |  |                        | 33.6 
|Transportation commitments                  |  |                        | 33.9 
|Operating leases                            |  |                        | 11.1 
|Risk management contract premiums(4)        |  |                        | 0.8  
|Accrued long-term incentive compensation(5) |  |                        | -    
|Total contractual commitments               |  |                        | 152.8





| | (1) | Long-term and short-term debt.
| | --- | ------------------------------

| | (2) | Fixed interest payments on senior notes.
| | --- | ----------------------------------------

| | (3) | Contribution commitments to a restricted reclamation fund associated with the Redwater property.
| | --- | ------------------------------------------------------------------------------------------------

| | (4) | Fixed premiums to be paid in future periods on certain commodity risk management contracts.
| | --- | -------------------------------------------------------------------------------------------

| | (5) | Liabilities under the RSU & PSU Plan represent the total amount expected to be paid out on
vesting.
| | --- | ---------------------------------------------------------------------------------------------------



Identification of Audit Committee



The Registrant has a separately designated
standing audit committee established in accordance with Section 3(a)(58)(A) of the Exchange Act. The members of the Audit
Committee are Fred J. Dyment (Chairman), Walter DeBoni, James C. Houck and Kathleen M. O'Neill.













UNDERTAKING
AND CONSENT TO SERVICE OF PROCESS



| | A. | Undertaking
| | -- | -----------



The Registrant undertakes to make available,
in person or by telephone, representatives to respond to inquiries made by the Commission staff, and to furnish promptly, when
requested to do so by the Commission staff, information relating to: the securities registered pursuant to Form 40-F; the securities
in relation to which the obligation to file an annual report on Form 40-F arises; or transactions in said securities.



| | B. | Consent to Service of Process
| | -- | -----------------------------



A Form F-X signed by the Registrant and
its agent for service of process was previously filed with the Commission in connection with the Common Shares (formerly Trust
Units of ARC Energy Trust) in relation to which the obligation to file this report arises.



Any change to the name or address of the
agent for service of process of the Registrant shall be communicated promptly to the Commission by an amendment to the Form F-X
referencing the file number of the Registrant.













SIGNATURES



Pursuant to the requirements
of the Exchange Act, the Registrant certifies that it meets all of the requirements for filing on Form 40-F and has duly caused
this annual report to be signed on its behalf by the undersigned, thereto duly authorized.





| |  | ARC RESOURCES LTD.
| |  | ------------------
| |  | (the Registrant)  
| |  |                   
| |  | By:               
| |  |                   
| |  |                   
| |  |                   
| |  | Date:             













Index to Exhibits



|Exhibit Number | Description                                                                                                                                                                                                    
|-------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|               |                                                                                                                                                                                                                
|99.1           | Annual Information Form for the fiscal year ended December 31, 2011.                                                                                                                                           
|               |                                                                                                                                                                                                                
|99.2           | Consolidated Financial Statements for the fiscal year ended December 31, 2011 (incorporated by reference to Exhibit 99.1 of Form 6-K filed with the Securities and Exchange Commission on February 9, 2012)    
|               |                                                                                                                                                                                                                
|99.3           | Management's Discussion and Analysis for the fiscal year ended December 31, 2011 (incorporated by reference to Exhibit 99.2 of Form 6-K filed with the Securities and Exchange Commission on February 9, 2012).
|               |                                                                                                                                                                                                                
|99.4           | Certification of Chief Executive Officer pursuant to Rule 13a-14(a) or 15d-14(a) of the Securities Exchange Act of 1934.                                                                                       
|               |                                                                                                                                                                                                                
|99.5           | Certification of Chief Financial Officer pursuant to Rule 13a-14(a) or 15d-14(a) of the Securities Exchange Act of 1934.                                                                                       
|               |                                                                                                                                                                                                                
|99.6           | Certifications of Chief Executive Officer pursuant to Rule 13(a)-14(b) and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. 1350).                                                  
|               |                                                                                                                                                                                                                
|99.7           | Certifications of Chief Financial Officer pursuant to Rule 13(a)-14(b) and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. 1350).                                                  
|               |                                                                                                                                                                                                                
|99.8           | Consent of Deloitte & Touche LLP, Independent Registered Chartered Accountants.                                                                                                                                
|               |                                                                                                                                                                                                                
|99.9           | Consent of GLJ Petroleum Consultants Ltd. to the inclusion of the Report dated February 15, 2012 evaluating the reserves and resources of ARC Resources Ltd.