UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No.     )*

JONES ENERGY, INC.

(Name of Issuer)

Class A Common Stock, $0.001 par value per share

(Title of Class of Securities)

48019R108

(CUSIP Number)

February 23, 2015

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

¨ Rule 13d-1(b)

x Rule 13d-1(c)

¨ Rule 13d-1(d)

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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ITEM 3.

Not applicable.

Ownership (a-c)

The ownership information presented below represents beneficial ownership of Common Stock of the Issuer as of the date of this filing, based upon 25,208,402 shares of Common Stock outstanding as of February 23, 2015.

GSO Special Situations Fund LP, GSO Special Situations Overseas Master Fund Ltd. and GSO Energy Market Opportunities Fund LP (collectively, the “GSO Funds”) are the record holders of 797,009, 790,293 and 793,651 shares of Common Stock, respectively.

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GSO Special Situations Overseas Fund Ltd. is the majority shareholder of GSO Special Situations Overseas Master Fund Ltd. and may be deemed to beneficially own the shares of Common Stock held of record by GSO Special Situations Overseas Master Fund Ltd.

GSO Capital Partners LP is the investment manager of each of GSO Special Situations Fund LP, GSO Special Situations Overseas Fund Ltd. and GSO Special Situations Overseas Master Fund LP. GSO Advisor Holdings L.L.C. is the general partner of GSO Capital Partners LP. Blackstone Holdings I L.P. is the sole member of GSO Advisor Holdings L.L.C.

GSO Energy Market Opportunities Associates LLC is the general partner of GSO Energy Market Opportunities Fund LP. GSO Holdings I L.L.C. is the managing member of GSO Energy Market Opportunities Associates LLC. Blackstone Holdings II L.P. is the managing member of GSO Holdings I L.L.C. with respect to shares of Common Stock that may be deemed to be beneficially owned by GSO Energy Market Opportunities Associates LLC.

Blackstone Holdings I/II GP Inc. is the general partner of each of Blackstone Holdings I L.P. and Blackstone Holdings II L.P. The Blackstone Group L.P. is the controlling shareholder of Blackstone Holdings I/II GP Inc. Blackstone Group Management L.L.C. is the general partner of The Blackstone Group L.P. Blackstone Group Management L.L.C. is wholly-owned by Blackstone’s senior managing directors and controlled by its founder, Stephen A. Schwarzman.

In addition, each of Bennett J. Goodman, J. Albert Smith III and Douglas I. Ostrover may be deemed to have shared voting, investment and/or dispositive power with respect to the shares of Common Stock held by the GSO Funds.

Each Reporting Person expressly disclaims any assertion or presumption that it and the other persons on whose behalf this statement is filed or who are otherwise party to the Joint Filing Agreement (as filed hereto as Exhibit 99) constitute a “group” for the purposes of Sections 13(d) and 13(g) of the Securities Exchange Act of 1934, as amended (the “Act”) and the rules thereunder. The filing of this statement should not be construed to be an admission that any member of the Reporting Persons are members of a “group” for the purposes of Sections 13(d) and 13(g) of the Act.

Not applicable.

Not applicable.

Not applicable.

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Not applicable.

Not applicable.

ITEM 10. Certification

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: March 5, 2015

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LIST OF EXHIBITS

Exhibit 24.1

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, BENNETT J. GOODMAN, hereby make, constitute and appoint MARISA BEENEY, acting individually, as my agent and attorney-in-fact for the purpose of executing in my name, (a) in my personal capacity or (b) in my capacity as an executive, member of or in other capacities with GSO Capital Partners LP, GSO Capital Advisors LLC or GSO / Blackstone Debt Funds Management LLC and each of their affiliates or entities advised by me, GSO Capital Partners LP, GSO Capital Advisors LLC or GSO / Blackstone Debt Funds Management LLC, all documents, certificates, instruments, statements, filings and agreements (“documents”) to be filed with or delivered to any foreign or domestic governmental or regulatory body or required or requested by any other person or entity pursuant to any legal or regulatory requirement relating to the acquisition, ownership, management or disposition of securities, futures contracts or other investments, and any other documents relating or ancillary thereto, including without limitation all documents relating to filings with any stock exchange, self-regulatory association, the Commodities Futures Trading Commission and National Futures Association, the United States Securities and Exchange Commission (the “SEC”) pursuant to the Securities Act of 1933 or the Securities Exchange Act of 1934 (the “Act”) and the rules and regulations promulgated thereunder, including all documents relating to the beneficial ownership of securities required to be filed with the SEC pursuant to Section 13(d) or Section 16(a) of the Act and any information statements on Form 13F required to be filed with the SEC pursuant to Section 13(f) of the Act, including without limitation Form 3, 4, 5, 144, or Schedules 13D, 13F and 13G and any amendments to said forms or schedules, in each case, as determined by such person to be necessary or appropriate. Any such determination shall be conclusively evidenced by such person’s execution, delivery, furnishing and/or filing of the applicable document.

All past acts of the attorneys-in-fact in furtherance of the foregoing are hereby ratified and confirmed.

This power of attorney shall be valid from the date hereof until the date revoked in writing by the undersigned, and this power of attorney does not revoke or replace any other power of attorney that the undersigned has previously granted.

IN WITNESS WHEREOF, I have executed this instrument as of the 8th day of June, 2010.

Exhibit 24.2

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, J. ALBERT SMITH III, hereby make, constitute and appoint MARISA BEENEY, acting individually, as my agent and attorney-in-fact for the purpose of executing in my name, (a) in my personal capacity or (b) in my capacity as an executive, member of or in other capacities with GSO Capital Partners LP, GSO Capital Advisors LLC or GSO / Blackstone Debt Funds Management LLC and each of their affiliates or entities advised by me, GSO Capital Partners LP, GSO Capital Advisors LLC or GSO / Blackstone Debt Funds Management LLC, all documents, certificates, instruments, statements, filings and agreements (“documents”) to be filed with or delivered to any foreign or domestic governmental or regulatory body or required or requested by any other person or entity pursuant to any legal or regulatory requirement relating to the acquisition, ownership, management or disposition of securities, futures contracts or other investments, and any other documents relating or ancillary thereto, including without limitation all documents relating to filings with any stock exchange, self-regulatory association, the Commodities Futures Trading Commission and National Futures Association, the United States Securities and Exchange Commission (the “SEC”) pursuant to the Securities Act of 1933 or the Securities Exchange Act of 1934 (the “Act”) and the rules and regulations promulgated thereunder, including all documents relating to the beneficial ownership of securities required to be filed with the SEC pursuant to Section 13(d) or Section 16(a) of the Act and any information statements on Form 13F required to be filed with the SEC pursuant to Section 13(f) of the Act, including without limitation Form 3, 4, 5, 144, or Schedules 13D, 13F and 13G and any amendments to said forms or schedules, in each case, as determined by such person to be necessary or appropriate. Any such determination shall be conclusively evidenced by such person’s execution, delivery, furnishing and/or filing of the applicable document.

All past acts of the attorneys-in-fact in furtherance of the foregoing are hereby ratified and confirmed.

This power of attorney shall be valid from the date hereof until the date revoked in writing by the undersigned, and this power of attorney does not revoke or replace any other power of attorney that the undersigned has previously granted.

IN WITNESS WHEREOF, I have executed this instrument as of the 8th day of June, 2010.

Exhibit 24.3

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, DOUGLAS I. OSTROVER, hereby make, constitute and appoint MARISA BEENEY, acting individually, as my agent and attorney-in-fact for the purpose of executing in my name, (a) in my personal capacity or (b) in my capacity as an executive, member of or in other capacities with GSO Capital Partners LP, GSO Capital Advisors LLC or GSO / Blackstone Debt Funds Management LLC and each of their affiliates or entities advised by me, GSO Capital Partners LP, GSO Capital Advisors LLC or GSO / Blackstone Debt Funds Management LLC, all documents, certificates, instruments, statements, filings and agreements (“documents”) to be filed with or delivered to any foreign or domestic governmental or regulatory body or required or requested by any other person or entity pursuant to any legal or regulatory requirement relating to the acquisition, ownership, management or disposition of securities, futures contracts or other investments, and any other documents relating or ancillary thereto, including without limitation all documents relating to filings with any stock exchange, self-regulatory association, the Commodities Futures Trading Commission and National Futures Association, the United States Securities and Exchange Commission (the “SEC”) pursuant to the Securities Act of 1933 or the Securities Exchange Act of 1934 (the “Act”) and the rules and regulations promulgated thereunder, including all documents relating to the beneficial ownership of securities required to be filed with the SEC pursuant to Section 13(d) or Section 16(a) of the Act and any information statements on Form 13F required to be filed with the SEC pursuant to Section 13(f) of the Act, including without limitation Form 3, 4, 5, 144, or Schedules 13D, 13F and 13G and any amendments to said forms or schedules, in each case, as determined by such person to be necessary or appropriate. Any such determination shall be conclusively evidenced by such person’s execution, delivery, furnishing and/or filing of the applicable document.

All past acts of the attorneys-in-fact in furtherance of the foregoing are hereby ratified and confirmed.

This power of attorney shall be valid from the date hereof until the date revoked in writing by the undersigned, and this power of attorney does not revoke or replace any other power of attorney that the undersigned has previously granted.

IN WITNESS WHEREOF, I have executed this instrument as of the 8th day of June, 2010.

Exhibit 99

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with each other on behalf of each of them of such a statement on Schedule 13G with respect to the common stock beneficially owned by each of them of Jones Energy Inc. This Joint Filing Agreement shall be included as an Exhibit to such Schedule 13G.

IN WITNESS WHEREOF, the undersigned hereby execute this Joint Filing Agreement as of the 5th day of March, 2015.