UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF

THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of Earliest Event Reported): June 5, 2012 (June 5, 2012)

CARBON NATURAL GAS COMPANY

(Exact name of registrant as specified in charter)

(720) 407-7043

(Registrant’s telephone number including area code)

(Former Name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Section 8               Other Events

Item 8.01               Other Events

Nytis Exploration Company LLC (“NEC”), a subsidiary of Carbon Natural Gas Company, has agreed on the principal terms of an amendment to its credit facility with Bank of Oklahoma.  In connection with the amendment, Bank of Oklahoma reaffirmed the borrowing base at $20 million and the maximum credit available for hedging arrangements under the credit facility is $8.0 million.  Further, Bank of Oklahoma has agreed to waive the funded debt ratio covenant during the remainder of 2012 and the minimum interest rate has increased 25 basis points (from 4.5% to 4.75% per annum) during that same period.  Other applicable credit spreads under the facility were also increased 25 basis points for the remainder of 2012.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this Report to be signed on its behalf by the undersigned, hereunto duly authorized.

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