Exhibit 5.1

Office of General Counsel

PAR Technology Corporation

8383 Seneca Turnpike

New Hartford, New York 13413-4991

June 17, 2020

PAR Technology Corporation

8383 Seneca Turnpike

New Hartford, New York 13413-4991

Re: PAR Technology Corporation Registration Statement on Form S-8

Ladies and Gentlemen:

I am Vice President, General Counsel and Secretary of PAR Technology Corporation, a Delaware corporation (the “Company”). I am providing the opinion set forth below in connection with the filing by the Company of a Registration Statement on Form S-8 (the “Registration Statement”) with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), in connection with the subsequent offer and sale of 854,371 shares of the Company’s common stock, par value $0.02 per share (“Common Stock”), that may be issued pursuant to the Amended and Restated PAR Technology Corporation 2015 Equity Incentive Plan, as amended June 4, 2020 (the “2015 Plan”), and the 67,273 shares of Common Stock reserved for issuance upon vesting of restricted stock units issued by the Company in connection with its assumption of awards granted by AccSys, LLC under the AccSys, LLC Phantom Equity Plan (the “Phantom Equity Plan”).

In connection with the below opinion, I have examined the Registration Statement, the 2015 Plan, the Phantom Equity Plan, and the originals, or photostatic or certified copies, of instruments, documents, certifications, and records as I have deemed relevant and necessary or appropriate to provide the opinion set forth below. In providing the opinion, I have assumed the genuineness of all signatures, the legal capacity of all natural persons, the authenticity of all documents submitted to me as originals and the conformity to original documents of all documents submitted to me as copies.

Based upon and subject to the foregoing, I am of the opinion that, following the effectiveness of the Registration Statement under the Securities Act, the shares of Common Stock issuable under the 2015 Plan and the Phantom Equity Plan, when issued and sold in accordance with the respective provisions thereof, will be validly issued, fully paid and nonassessable.

The opinion does not relate to matters involving the laws of any jurisdiction other than the Delaware General Corporation Law (the “DGCL”). The opinion is limited to the effect of the current state of the law of the DGCL and the facts as they currently exist. I assume no obligation to supplement the opinion in the event of future changes in such law or the interpretations thereof or such facts.

I consent to the filing of this opinion letter as Exhibit 5.1 to the Registration Statement with the Commission.

Very truly yours,

/s/ Cathy A. King, Esq.

Cathy A. King

Vice President, General Counsel and Secretary