Exhibit 5.1

MARTIN LIPTON HERBERT M. WACHTELL EDWARD D. HERLIHY DANIEL A. NEFF STEVEN A. ROSENBLUM SCOTT K. CHARLES JODI J. SCHWARTZ ADAM O. EMMERICH RALPH M. LEVENE ROBIN PANOVKA DAVID A. KATZ ILENE KNABLE GOTTS ANDREW J. NUSSBAUM RACHELLE SILVERBERG STEVEN A. COHEN DEBORAH L. PAUL DAVID C. KARP RICHARD K. KIM JOSHUA R. CAMMAKER MARK GORDON JEANNEMARIE O’BRIEN	STEPHEN R. DiPRIMA NICHOLAS G. DEMMO IGOR KIRMAN JONATHAN M. MOSES T. EIKO STANGE WILLIAM SAVITT GREGORY E. OSTLING DAVID B. ANDERS ADAM J. SHAPIRO NELSON O. FITTS JOSHUA M. HOLMES DAMIAN G. DIDDEN IAN BOCZKO MATTHEW M. GUEST DAVID E. KAHAN DAVID K. LAM BENJAMIN M. ROTH JOSHUA A. FELTMAN ELAINE P. GOLIN EMIL A. KLEINHAUS KARESSA L. CAIN	51 WEST  52ND  STREET NEW YORK, N.Y. 10019-6150 TELEPHONE: (212) 403-1000 FACSIMILE:    (212) 403-2000		RONALD C. CHEN BRADLEY R. WILSON GRAHAM W. MELI GREGORY E. PESSIN CARRIE M. REILLY MARK F. VEBLEN SARAH K. EDDY VICTOR GOLDFELD RANDALL W. JACKSON BRANDON C. PRICE KEVIN S. SCHWARTZ MICHAEL S. BENN ALISON Z. PREISS TIJANA J. DVORNIC JENNA E. LEVINE RYAN A. McLEOD ANITHA REDDY JOHN L. ROBINSON STEVEN WINTER EMILY D. JOHNSON JACOB A. KLING	RAAJ S. NARAYAN VIKTOR SAPEZHNIKOV MICHAEL J. SCHOBEL ELINA TETELBAUM ERICA E. AHO LAUREN M. KOFKE ZACHARY S. PODOLSKY RACHEL B. REISBERG MARK A. STAGLIANO CYNTHIA FERNANDEZ LUMERMANN CHRISTINA C. MA NOAH B. YAVITZ BENJAMIN S. ARFA NATHANIEL D. CULLERTON ERIC M. FEINSTEIN ADAM L. GOODMAN STEVEN R. GREEN MENG LU
		GEORGE A. KATZ (1965–1989) JAMES H. FOGELSON (1967–1991) LEONARD M. ROSEN (1965–2014) OF COUNSEL
		DAVID M. ADLERSTEIN ANDREW R. BROWNSTEIN WAYNE M. CARLIN BEN M. GERMANA SELWYN B. GOLDBERG PETER C. HEIN JB KELLY JOSEPH D. LARSON RICHARD G. MASON PHILIP MINDLIN THEODORE N. MIRVIS DAVID S. NEILL TREVOR S. NORWITZ	ERIC S. ROBINSON ERIC M. ROSOF JOHN F. SAVARESE MICHAEL J. SEGAL WON S. SHIN DAVID M. SILK ELLIOTT V. STEIN LEO E. STRINE, JR.* PAUL VIZCARRONDO, JR. JEFFREY M. WINTNER AMY R. WOLF MARC WOLINSKY
		* ADMITTED IN DELAWARE COUNSEL
		SUMITA AHUJA LOREN BRASWELL HEATHER D. CASTEEL FRANCO CASTELLI ANDREW J.H. CHEUNG PAMELA EHRENKRANZ ALINE R. FLODR KATHRYN GETTLES-ATWA LEDINA GOCAJ ADAM M. GOGOLAK	ANGELA K. HERRING MICHAEL W. HOLT DONGHWA KIM MARK A. KOENIG J. AUSTIN LYONS ALEXANDER S. MACKLER ALICIA C. McCARTHY JUSTIN R. ORR NEIL M. SNYDER JEFFREY A. WATIKER

September 12, 2025

Opendoor Technologies Inc.

410 N. Scottsdale Road, Suite 1600

Tempe, AZ  85281

Re: Registration Statement on Form S-8

Ladies and Gentlemen:

We have acted as special counsel to Opendoor Technologies Inc., a Delaware corporation (the “Company”), in connection with the Registration Statement on Form S-8 (the “Registration Statement”, which term does not include any other document or agreement whether or not specifically referred to therein or attached as an exhibit or schedule thereto), under the Securities Act of 1933, as amended (the “Securities Act”), relating to the issuance by the Company of up to 81,772,688 shares common stock, par value $0.0001 per share, of the Company (the “Shares”) which may be issued pursuant to the Nasdaq “inducement award” exception under Nasdaq Listing Rule 5635(c)(4), including the Inducement Awards (as defined in the Registration Statement).

In our capacity as special counsel to the Company and in connection with the opinion set forth herein, we have examined the originals, or duplicates or certified or conformed copies, of such corporate records, agreements, documents and other instruments, including the certificate of incorporation and bylaws of the Company, in each case, as amended through the date hereof, and have made such other investigations as we have deemed relevant and necessary in connection with the opinion set forth below. As to questions of fact material to this opinion, we have relied upon oral and written representations of officers and representatives of the Company and certificates or comparable documents of public officials and of officers and representatives of the Company.

In making such examination and rendering the opinion set forth below, we have assumed without verification the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to originals of all documents submitted to us as copies, and the legal capacity of all individuals executing any of the foregoing documents.

In rendering the opinion set forth below, we have also assumed that the Shares, when issued, will be duly authenticated by the transfer agent and registrar for the Shares and that the certificates, if any, evidencing the Shares to be issued will be manually signed by one of the authorized officers of the transfer agent and registrar for the Shares and registered by such transfer agent.

Based upon the foregoing, and subject to the qualifications, assumptions and limitations stated herein, we are of the opinion that when the Shares have been issued and delivered pursuant to the terms and conditions set forth in the Registration Statement, the Shares will be validly issued, duly authorized, fully paid and nonassessable.

We do not express any opinion herein concerning any law other than the Delaware General Corporation Law (including the statutory provisions, all applicable provisions of the Delaware Constitution and reported judicial decisions interpreting the foregoing). This opinion letter is being furnished solely in connection with the offer, sale and issuance of the Shares and may not be used, quoted, relied upon or otherwise referred to for any other purpose without our prior written consent.

We hereby consent to the filing of this opinion letter as Exhibit 5.1 to the Registration Statement. In giving such consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.

Very truly yours,

Wachtell, Lipton, Rosen & Katz