Exhibit 5.1

June 29, 2017

National General Holdings Corp.

59 Maiden Lane, 38th Floor

New York, New York 10038

Re:    Registration Statement on Form S-1

Ladies and Gentlemen:

We refer to the Registration Statement on Form S-1 (File No. 333-218910), as amended by Pre-Effective Amendment No. 1 being filed on the date hereof (the “Registration Statement”) by National General Holdings Corp., a Delaware corporation (the “Company”), with the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended (the “Securities Act”), relating to the resale from time to time of 12,295,430 shares of common stock, par value $0.01 per share (the “Common Stock”), by the selling stockholders referenced in the prospectus which forms a part of the Registration Statement.

This opinion letter is being delivered in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

In rendering the opinion set forth in this letter, we have examined and relied upon copies of the Registration Statement, the Company’s second amended and restated certificate of incorporation and amended and restated bylaws, each as in effect on the date hereof, and the resolutions adopted by the board of directors of the Company relating to the Registration Statement and the issuance of the Common Stock by the Company. We have also examined originals, or copies of originals certified to our satisfaction, of such agreements, documents, certificates and statements of the Company and other corporate documents and instruments, and have examined such questions of law, as we have considered relevant and necessary as a basis for this opinion letter. We have assumed the authenticity of all documents submitted to us as originals, the genuineness of all signatures, the legal capacity of all natural persons and the conformity with the original documents of any copies thereof submitted to us for our examination. As to facts relevant to the opinions expressed herein, we have relied, without independent investigation or verification, upon, and assumed the accuracy and completeness of, certificates, letters and oral and written statements and representations of public officials and officers and other representatives of the Company.

Sidley Austin (NY) LLP is a Delaware limited liability partnership doing business as Sidley Austin LLP and practicing in affiliation with other Sidley Austin partnerships.

National General Holdings Corp.

June 29, 2017

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Based on the foregoing, and subject to the qualifications and limitations set forth herein, we are of the opinion that the shares of Common Stock covered by the Registration Statement are validly issued, fully paid and non-assessable.

This opinion letter is limited to the General Corporation Law of the State of Delaware. We express no opinion as to the laws, rules or regulations of any other jurisdiction, including, without limitation, the federal laws of the United States of America or any state securities or blue sky laws.

We hereby consent to the filing of this opinion letter as an Exhibit to the Registration Statement and to all references to our Firm included in or made a part of the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.

Very truly yours,

/s/ Sidley Austin LLP

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