Wilson Sonsini Goodrich & Rosati Professional Corporation 900 South Capital of Texas Highway Las Cimas IV, Fifth Floor Austin, Texas 78746-5546 O: 512.338.5400 F: 512.338.5499

Exhibit 5.1

August 10, 2021

BigCommerce Holdings, Inc.

11305 Four Points Drive

Building II, Third Floor

Austin, Texas 78726

Re:    Registration Statement on Form S-8

Ladies and Gentlemen:

We have examined the Registration Statement on Form S-8 to be filed by you with the Securities and Exchange Commission on or about the date hereof (the “Registration Statement”) in connection with up to 195,339 shares of your Series 1 common stock, par value $0.0001 per share (the “Shares”), issuable pursuant to the BigCommerce Holdings, Inc. 2021 Inducement Equity Incentive Plan (the “Plan”). As your counsel for this matter, we have examined the proceedings taken and are familiar with the proceedings proposed to be taken by you in connection with the issuance and sale of the Shares pursuant to the Plan.

It is our opinion that, upon completion of the actions being taken, or contemplated by us as your counsel to be taken by you prior to the issuance of the Shares pursuant to the Registration Statement and the Plan and upon completion of the actions being taken in order to permit such transactions to be carried out in accordance with the general corporation law of the State of Delaware (including the statutory provisions, all applicable provisions of the Delaware Constitution and reported judicial decisions interpreting the foregoing), the Shares, when issued and sold in the manner referred to in the Plan, will be legally and validly issued, fully paid and nonassessable.

We consent to the use of this opinion as an exhibit to said Registration Statement and further consent to the use of our name wherever appearing in said Registration Statement, and any amendments thereto.

 

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