EX-31 Rule 13a-14(d)/15d-14(d) Certifications.





I, Nicholas Galeone, certify that:



1. I have reviewed this report on Form 10-K and all reports on
Form 10-D required to be filed in respect of the period covered by this report
on Form 10-K of the UBS Commercial Mortgage Trust 2018-C15 (the "Exchange
Act periodic reports");



2. Based on my knowledge, the Exchange Act periodic reports, taken
as a whole, do not contain any untrue statement of a material fact or omit to
state a material fact necessary to make the statements made, in light of the
circumstances under which such statements were made, not misleading with
respect to the period covered by this report;



3. Based on my knowledge, all of the distribution, servicing and
other information required to be provided under Form 10-D for the period
covered by this report is included in the Exchange Act periodic reports;



4. Based on my knowledge and the servicer compliance statements
required in this report under Item 1123 of Regulation AB, and except as
disclosed in the Exchange Act periodic reports, the servicers have fulfilled
their obligations under the servicing agreements in all material respects; and



5. All of the reports on assessment of compliance with servicing
criteria for asset-backed securities and their related attestation reports on
assessment of compliance with servicing criteria for asset-backed securities
required to be included in this report in accordance with Item 1122 of
Regulation AB and Exchange Act Rules 13a-18 and 15d-18 have been included as an
exhibit to this report, except as otherwise disclosed in this report. Any
material instances of noncompliance described in such reports have been
disclosed in this report on Form 10-K.



In giving the certifications above, I have reasonably relied on
information provided to me by the following unaffiliated parties:



Midland Loan Services, a Division of PNC Bank, National
Association, as Master Servicer, Midland Loan Services, a Division of PNC Bank,
National Association, as Special Servicer, Wells Fargo Bank, National
Association, as Trustee and Certificate Administrator, Wells Fargo Bank,
National Association, as Custodian, Pentalpha Surveillance LLC, as Operating
Advisor, Wells Fargo Bank, National Association, as Primary Servicer for the
Christiana Mall Mortgage Loan, Computershare Trust Company, National
Association, as Servicing Function Participant for the Certificate
Administrator on and after November 1, 2021, Computershare Trust Company,
National Association, as Servicing Function Participant for the Custodian on
and after November 1, 2021, Wells Fargo Bank, National Association, as Special
Servicer for the Christiana Mall Mortgage Loan, Wilmington Trust, National
Association, as Trustee for the Christiana Mall Mortgage Loan, Wells Fargo
Bank, National Association, as Custodian for the Christiana Mall Mortgage Loan,
CoreLogic Solutions, LLC, as Servicing Function Participant for the Christiana
Mall Mortgage Loan, Computershare Trust Company, National Association, as
Servicing Function Participant for the Custodian for the Christiana Mall
Mortgage Loan on and after November 1, 2021, Midland Loan Services, a Division
of PNC Bank, National Association, as Primary Servicer for the Pier 1 Imports
Headquarters Mortgage Loan, Midland Loan Services, a Division of PNC Bank,
National Association, as Special Servicer for the Pier 1 Imports Headquarters
Mortgage Loan, Wells Fargo Bank, National Association, as Trustee for the Pier
1 Imports Headquarters Mortgage Loan, Wells Fargo Bank, National Association,
as Custodian for the Pier 1 Imports Headquarters Mortgage Loan, Pentalpha
Surveillance LLC, as Operating Advisor for the Pier 1 Imports Headquarters
Mortgage Loan, Computershare Trust Company, National Association, as Servicing
Function Participant for the Custodian for the Pier 1 Imports Headquarters
Mortgage Loan on and after November 1, 2021, Wells Fargo Bank, National
Association, as Primary Servicer for the Ellsworth Place Mortgage Loan, Midland
Loan Services, a Division of PNC Bank, National Association, as Special
Servicer for the Ellsworth Place Mortgage Loan, Wilmington Trust, National
Association, as Trustee for the Ellsworth Place Mortgage Loan, Wells Fargo
Bank, National Association, as Custodian for the Ellsworth Place Mortgage Loan,
Park Bridge Lender Services LLC, as Operating Advisor for the Ellsworth Place
Mortgage Loan, CoreLogic Solutions, LLC, as Servicing Function Participant for
the Ellsworth Place Mortgage Loan, Computershare Trust Company, National Association,
as Servicing Function Participant for the Custodian for the Ellsworth Place
Mortgage Loan on and after November 1, 2021, Midland Loan Services, a Division
of PNC Bank, National Association, as Primary Servicer for the Nebraska
Crossing Mortgage Loan, Rialto Capital Advisors, LLC, as Special Servicer for
the Nebraska Crossing Mortgage Loan, Wells Fargo Bank, National Association, as
Trustee for the Nebraska Crossing Mortgage Loan, Wells Fargo Bank, National
Association, as Custodian for the Nebraska Crossing Mortgage Loan, Park Bridge
Lender Services LLC, as Operating Advisor for the Nebraska Crossing Mortgage
Loan, Computershare Trust Company, National Association, as Servicing Function
Participant for the Custodian for the Nebraska Crossing Mortgage Loan on and
after November 1, 2021, Midland Loan Services, a Division of PNC Bank, National
Association, as Primary Servicer for the Clevelander South Beach Mortgage Loan,
Rialto Capital Advisors, LLC, as Special Servicer for the Clevelander South
Beach Mortgage Loan, Wells Fargo Bank, National Association, as Trustee for the
Clevelander South Beach Mortgage Loan, Wells Fargo Bank, National Association,
as Custodian for the Clevelander South Beach Mortgage Loan, Park Bridge Lender
Services LLC, as Operating Advisor for the Clevelander South Beach Mortgage
Loan, Computershare Trust Company, National Association, as Servicing Function
Participant for the Custodian for the Clevelander South Beach Mortgage Loan on
and after November 1, 2021, Midland Loan Services, a Division of PNC Bank,
National Association, as Primary Servicer for the Regency Properties Portfolio
Mortgage Loan, Rialto Capital Advisors, LLC, as Special Servicer for the
Regency Properties Portfolio Mortgage Loan, Wells Fargo Bank, National Association,
as Trustee for the Regency Properties Portfolio Mortgage Loan, Wells Fargo
Bank, National Association, as Custodian for the Regency Properties Portfolio
Mortgage Loan, Park Bridge Lender Services LLC, as Operating Advisor for the
Regency Properties Portfolio Mortgage Loan, Computershare Trust Company,
National Association, as Servicing Function Participant for the Custodian for
the Regency Properties Portfolio Mortgage Loan on and after November 1, 2021,
Midland Loan Services, a Division of PNC Bank, National Association, as Primary
Servicer for the Staples Strategic Industrial Mortgage Loan, CWCapital Asset
Management LLC, as Special Servicer for the Staples Strategic Industrial
Mortgage Loan, Wells Fargo Bank, National Association, as Trustee for the
Staples Strategic Industrial Mortgage Loan, Wells Fargo Bank, National
Association, as Custodian for the Staples Strategic Industrial Mortgage Loan,
Pentalpha Surveillance LLC, as Operating Advisor for the Staples Strategic
Industrial Mortgage Loan, Computershare Trust Company, National Association, as
Servicing Function Participant for the Custodian for the Staples Strategic
Industrial Mortgage Loan on and after November 1, 2021, Midland Loan Services,
a Division of PNC Bank, National Association, as Primary Servicer for the
ExchangeRight Net Leased Portfolio 24 Mortgage Loan, 3650 REIT Loan Servicing
LLC, as Special Servicer for the ExchangeRight Net Leased Portfolio 24 Mortgage
Loan, Wells Fargo Bank, National Association, as Trustee for the ExchangeRight
Net Leased Portfolio 24 Mortgage Loan, Wells Fargo Bank, National Association,
as Custodian for the ExchangeRight Net Leased Portfolio 24 Mortgage Loan, Park
Bridge Lender Services LLC, as Operating Advisor for the ExchangeRight Net
Leased Portfolio 24 Mortgage Loan, Computershare Trust Company, National
Association, as Servicing Function Participant for the Custodian for the
Exchange Right Net Leased Portfolio 24 Mortgage Loan on and after November 1,
2021, KeyBank National Association, as Primary Servicer for the Saint Louis
Galleria Mortgage Loan, LNR Partners, LLC, as Special Servicer for the Saint
Louis Galleria Mortgage Loan, Wells Fargo Bank, National Association, as
Trustee for the Saint Louis Galleria Mortgage Loan, Wells Fargo Bank, National
Association, as Custodian for the Saint Louis Galleria Mortgage Loan, Pentalpha
Surveillance LLC, as Operating Advisor for the Saint Louis Galleria Mortgage
Loan, Computershare Trust Company, National Association, as Servicing Function
Participant for the Custodian for the Saint Louis Galleria Mortgage Loan on and
after November 1, 2021, Midland Loan Services, a Division of PNC Bank, National
Association, as Primary Servicer for the Great Value Storage Portfolio Mortgage
Loan, Midland Loan Services, a Division of PNC Bank, National Association, as
Special Servicer for the Great Value Storage Portfolio Mortgage Loan, Wells
Fargo Bank, National Association, as Trustee for the Great Value Storage
Portfolio Mortgage Loan, Wells Fargo Bank, National Association, as Custodian
for the Great Value Storage Portfolio Mortgage Loan, Park Bridge Lender
Services LLC, as Operating Advisor for the Great Value Storage Portfolio
Mortgage Loan, Computershare Trust Company, National Association, as Servicing
Function Participant for the Custodian for the Great Value Storage Portfolio
Mortgage Loan on and after November 1, 2021, Midland Loan Services, a Division
of PNC Bank, National Association, as Primary Servicer for the Heartland Dental
Medical Office Portfolio Mortgage Loan, Rialto Capital Advisors, LLC, as
Special Servicer for the Heartland Dental Medical Office Portfolio Mortgage
Loan, Wilmington Trust, National Association, as Trustee for the Heartland
Dental Medical Office Portfolio Mortgage Loan, Wells Fargo Bank, National Association,
as Custodian for the Heartland Dental Medical Office Portfolio Mortgage Loan,
Park Bridge Lender Services LLC, as Operating Advisor for the Heartland Dental
Medical Office Portfolio Mortgage Loan, and Computershare Trust Company,
National Association, as Servicing Function Participant for the Custodian for
the Heartland Dental Medical Office Portfolio Mortgage Loan on and after
November 1, 2021.







Dated:
March14,
2022





/s/ Nicholas Galeone

Nicholas Galeone

President

(senior
officer in charge of securitization of the depositor)