Exhibit 4.1


 





NUMBER UNITS

U-


 


SEE REVERSE FOR CERTAIN

DEFINITIONS


CUSIP [●]


 


ONE MADISON CORPORATION


 


UNITS CONSISTING OF ONE CLASS A ORDINARY
SHARE

AND ONE-HALF OF ONE WARRANT, EACH WHOLE WARRANT ENTITLING THE HOLDER TO PURCHASE ONE CLASS A

ORDINARY SHARE


 


THIS CERTIFIES THAT __________________ is the
owner of _______ Units.


 


Each Unit (“Unit”) consists
of one (1) Class A Ordinary Share, par value $0.0001 per share (“Ordinary Share”), of One Madison Corporation,
a Cayman Islands exempted company (the “Company”), and one-half of one warrant (the “Warrant”).
Each whole warrant entitles the holder to purchase one Ordinary Share for $11.50 per share (subject to adjustment). Each Warrant
will become exercisable on the later of (i) thirty (30) days after the Company’s completion of a merger, share exchange,
asset acquisition, share purchase, reorganization or other similar business combination with one or more businesses (each a “Business
Combination”), or (ii) twelve (12) months from the closing of the Company’s initial public offering, and will
expire unless exercised before 5:00 p.m., New York City Time, on the date that is five (5) years after the date on which the Company
completes its initial Business Combination, or earlier upon redemption or liquidation (the “Expiration Date”).
The Ordinary Shares and Warrants comprising the Units represented by this certificate are not transferable separately prior to
____________, 2018, unless Credit Suisse Securities (USA) LLC and Merrill Lynch, Pierce, Fenner & Smith Incorporated elect
to allow separate trading earlier, subject to the Company’s filing of a Current Report on Form 8-K with the Securities and
Exchange Commission containing an audited balance sheet reflecting the Company’s receipt of the gross proceeds of the initial
public offering and issuing a press release announcing when separate trading will begin. The terms of the Warrants are governed
by a Warrant Agreement, dated as of ____________, 2018, between the Company and Continental Stock Transfer & Trust
Company, as Warrant Agent, and are subject to the terms and provisions contained therein, all of which terms and provisions the
holder of this certificate consents to by acceptance hereof. Copies of the Warrant Agreement are on file at the office of the
Warrant Agent at 17 Battery Place, New York, New York 10004, and are available to any Warrant holder on written request and without
cost.


 


This certificate is not valid unless countersigned
by the Transfer Agent and Registrar of the Company.


 




     


     


    

  


This certificate shall be governed by and construed
in accordance with the internal laws of the State of New York. Witness the facsimile signature of its duly authorized officers.


 


	By:	 	 	By:	 
	 	Name:	 	 	Name:
	 	Title:Secretary	 	 	Title:President


 




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One Madison Corporation


 


The Company will furnish without charge to each
unitholder who so requests, a statement of the powers, designations, preferences and relative, participating, optional or other
special rights of each class of equity or series thereof of the Company and the qualifications, limitations, or restrictions of
such preferences and/or rights.


 


The following abbreviations, when used in the
inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable
laws or regulations:


 


	TEN COM	—   as tenants in common	UNIF GIFT MIN ACT—   ___________ Custodian
	 	 	___________
	TEN ENT	—   as tenants by the entireties	(Cust)
	 	 	(Minor)
	 	 	Under Uniform Gifts to Minors
	JT TEN	—   as joint tenants with right of survivorship and not as	 
	 	tenants in common	Act
	 	 	(State)


 


Additional abbreviations may also be used though
not in the above list.


 


For value received, ________ hereby sell,
assign and transfer unto ________


 


PLEASE INSERT SOCIAL SECURITY OR

OTHER


IDENTIFYING NUMBER OF ASSIGNEE


 





	 
	(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)
	 
	 




 





	 	Units represented by the within Certificate, and do hereby irrevocably constitute and 
	appoint	 




 





	 	Attorney to transfer the said Units on the books of the within named Corporation 
	with full power of substitution in the premises.	 




 





	Dated _______________







 


	 	 	 
	 	Notice:	The signature to this assignment
must correspond with the name as written upon the face of the certificate in every particular, without alteration or enlargement
or any change whatever.


 


Signature(s) Guaranteed:


 




 


THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION
(BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION
PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15 UNDER THE SECURITIES ACT OF 1933, AS AMENDED).





 




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In each case, as more fully described in the
Company’s final prospectus dated ________________, the holder(s) of this certificate shall be entitled to receive a pro-rata
portion of certain funds held in the trust account established in connection with its initial public offering only (i) in the event
that the Company redeems the Class A Ordinary Shares sold in its initial public offering and liquidates because it does not consummate
an initial business combination within 24 months from the closing of its initial public offering or (ii) if the holder(s) (who
is not a director or officer of the Company and was not a shareholder of the Company immediately prior to the closing of its initial
public offering) seek(s) to redeem for cash his, her or its respective Class A Ordinary Shares in connection with (A) an amendment
to the Company’s Amended and Restated Memorandum and Articles of Association that would affect the substance or timing of
the Company's obligation to redeem 100% of the Class A Ordinary Shares if it does not consummate an initial business combination
within 24 months from the closing of its initial public offering, or (B) a tender offer (or proxy solicitation, solely in the event
the Company seeks shareholder approval of the proposed initial business combination) setting forth the details of a proposed initial
business combination. In no other circumstances shall the holder(s) have any right or interest of any kind in or to the trust account.


 







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