Exhibit 99.1

Ernst & Young LLP One Manhattan West New York, NY 10001

Tel: +1 212 773 3000 ey.com

Report of Independent Accountants on Applying Agreed-Upon Procedures

Citigroup Commercial Mortgage Securities Inc. (the “Depositor”)

Citi Real Estate Funding Inc.

Citigroup Global Markets Inc.

JPMorgan Chase Bank, National Association

J.P. Morgan Securities LLC

(collectively, the “Specified Parties”)

Commercial Mortgage Pass-Through Certificates, Series 2026-PRM9 (the “Certificates”)

We have performed the procedures enumerated in Attachment A, which were agreed to and acknowledged as appropriate by the Specified Parties, for the intended purpose of assisting the Specified Parties in evaluating the accuracy of certain information with respect to the Mortgage Loans (as defined herein) contained on the Data Files (as defined herein) (the “Subject Matter”) relating to the Issuing Entity’s securitization transaction as of 27 October 2026. This report may not be suitable for any other purpose. The procedures performed may not address all of the items of interest to a user of the report and may not meet the needs of all users of the report and, as such, users are responsible for determining whether the procedures performed are appropriate for their purposes. The appropriateness of these procedures is solely the responsibility of the Specified Parties identified in this report. No other party acknowledged the appropriateness of the procedures. Consequently, we make no representation regarding the appropriateness of the procedures described in Attachment A, either for the purpose for which this report has been requested or for any other purpose.

The procedures performed and our associated findings are included in Attachment A.

For the purpose of the procedures described in this report, the Depositor provided us with:

Page 2 of 3

The procedures included in Attachment A were limited to comparing or recalculating certain information that is further described in Attachment A. The Depositor is responsible for the Subject Matter, Data Files, Source Documents, Compared Characteristics, Recalculated Characteristics, Provided Characteristics, Draft Preliminary Offering Circular and the determination of the instructions, assumptions and methodologies that are described herein. We were not requested to perform, and we have not performed, any procedures other than those listed in Attachment A with respect to the Data Files. We have not verified, and we make no representation as to, the appropriateness, accuracy, completeness or reasonableness of the Source Documents, Provided Characteristics, Draft Preliminary Offering Circular or any other information provided to us by the Depositor upon which we relied in forming our findings. Accordingly, we make no representation and express no opinion or conclusion as to: (a) the existence of the Mortgage Loans, (b) questions of legal or tax interpretation or (c) the appropriateness, accuracy, completeness or reasonableness of any instructions, assumptions and methodologies provided to us by the Depositor that are described in this report. We undertake no responsibility to update this report for events and circumstances occurring after the date hereof.

This agreed-upon procedures engagement was conducted in accordance with attestation standards established by the American Institute of Certified Public Accountants (the “AICPA”). An agreed-upon procedures engagement involves the practitioner performing specific procedures that the Specified Parties have agreed to and acknowledged to be appropriate for the purpose of the engagement and reporting on findings based on the procedures performed.

We were not engaged to, and did not, conduct an examination or review, the objective of which would be the expression of an opinion or conclusion, respectively, on the Subject Matter or on any of the items referred to herein. Accordingly, we do not express such an opinion or conclusion. Had we performed additional procedures, other matters might have come to our attention that would have been reported to you.

The agreed-upon procedures described in this report were not performed for the purpose of:

Page 3 of 3

We are required to be independent of the Depositor and to meet our other ethical responsibilities, as applicable for agreed-upon procedures engagements set forth in the Preface: Applicable to All Members and Part 1 – Members in Public Practice of the Code of Professional Conduct established by the AICPA. Independence requirements for agreed-upon procedures engagements are less restrictive than independence requirements for audit and other attestation services.

This report is intended solely for the information and use of the Specified Parties and is not intended to be, and should not be, used by anyone other than the Specified Parties. It is not intended to be, and should not be, used by any other person or entity, including investors and rating agencies, who are not identified in the report as Specified Parties, but who may have access to this report as required by law or regulation.

/s/ Ernst & Young LLP

27 October 2026

Attachment A Page 1 of 6

Background

For the purpose of the procedures described in this report, the Depositor indicated that:

For the purpose of the procedures described in this report, the Depositor indicated certain information on the Data Files is shown on an aggregate basis of the Mortgage Loans, such aggregate information is hereinafter referred to as the “Pool Level Information.” All references and recalculations related to the Pool Level Information relate to the aggregate information for the Issuing Entity.

Procedures performed and our associated findings

Using the information in the Source Documents, we compared the Compared Characteristics listed on Exhibit 2 to Attachment A, as shown on the Preliminary Data File, to the corresponding information in the Source Documents indicated on Exhibit 2 to Attachment A, subject to the instructions, assumptions and methodologies stated in the notes on Exhibit 2 to Attachment A. If more than one Source Document is listed for a Compared Characteristic, the Depositor instructed us to note agreement if the value on the Preliminary Data File for the Compared Characteristic agreed with the corresponding information in at least one of the Source Documents listed for such Compared Characteristic on Exhibit 2 to Attachment A (except as described in the notes on Exhibit 2 to Attachment A). We performed no procedures to reconcile any differences that may exist between various Source Documents for any of the Compared Characteristics listed on Exhibit 2 to Attachment A.

We performed certain procedures on earlier versions of the Data Files and communicated differences prior to being provided the Data Files which were subjected to the procedures as described herein.

Attachment A Page 2 of 6

Using information on the:

we compared each Compared Characteristic listed on Exhibit 2 to Attachment A, as shown on the Final Data File, to the corresponding information on the Updated Data File and found such information to be in agreement.

as shown on the Final Data File, we recalculated the “Original Term to Maturity (Months)” of each Mortgage Loan. We compared this recalculated information to the corresponding information on the Final Data File and found such information to be in agreement.

as shown on the Final Data File, we recalculated the “Remaining Term to Maturity (Months)” of each Mortgage Loan. We compared this recalculated information to the corresponding information on the Final Data File and found such information to be in agreement.

Attachment A Page 3 of 6

We compared this information to the corresponding information on the Final Data File and found such information to be in agreement.

as shown on the Final Data File, and the calculation methodologies provided by the Depositor described in the succeeding paragraph(s) of this Item, we recalculated the:

of each Mortgage Loan. We compared this recalculated information to the corresponding information on the Final Data File and found such information to be in agreement.

For the purpose of this procedure, the Depositor instructed us to recalculate the “Mortgage Loan Monthly Debt Service Payment” of each Mortgage Loan as 1/12^th of the product, rounded to two decimal places, of:

Attachment A Page 4 of 6

8. (continued)

For the purpose of this procedure, the Depositor instructed us to recalculate the “Mortgage Loan Annual Debt Service Payment” of each Mortgage Loan as twelve (12) times the “Mortgage Loan Monthly Debt Service Payment,” as shown on the Final Data File.

For purpose of the procedure for the Pool Level Information, the Depositor instructed us to recalculate the characteristics listed in i. and ii. above on an aggregate basis, using the recalculated values from this Item for each Mortgage Loan.

as shown on the Final Data File, and the applicable calculation methodologies and assumptions described in the Draft Preliminary Offering Circular, we recalculated the:

of each Mortgage Loan and Pool Level Information, and with respect to iii. through v. above, of each Property. We compared this recalculated information to the corresponding information on the Final Data File and found such information to be in agreement.

For the purpose of this procedure, the Depositor instructed us to:

Attachment A Page 5 of 6

as shown on the Final Data File, we recalculated the:

of each Mortgage Loan, each Property and the Pool Level Information. We compared this recalculated information to the corresponding information on the Final Data File and found such information to be in agreement.

as shown on the Final Data File, we recalculated the:

of each Mortgage Loan, each Property and Pool Level Information. We compared this recalculated information to the corresponding information on the Final Data File and found such information to be in agreement.

Attachment A Page 6 of 6

as shown on the Final Data File, we recalculated the:

of each Mortgage Loan, each Property and the Pool Level Information. We compared this recalculated information to the corresponding information on the Final Data File and found such information to be in agreement.

Exhibit 1 to Attachment A

Page 1 of 2

Source Documents

Mortgage Loan Source Documents

Property Source Documents

Exhibit 1 to Attachment A

Page 2 of 2

Property Source Documents (continued)

Note:

Exhibit 2 to Attachment A
Page 1 of 16

Compared Characteristics and Source Documents

Property Information:

Exhibit 2 to Attachment A
Page 2 of 16

Property Information: (continued)

Exhibit 2 to Attachment A
Page 3 of 16

Third Party Information:

Exhibit 2 to Attachment A
Page 4 of 16

Underwriting Information:

Exhibit 2 to Attachment A
Page 5 of 16

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 6 of 16

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 7 of 16

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 8 of 16

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 9 of 16

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 10 of 16 

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 11 of 16 

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 12 of 16

Underwriting Information: (continued)

Exhibit 2 to Attachment A
Page 13 of 16 

Reserve and Escrow Information:

Mortgage Loan Information:

Exhibit 2 to Attachment A
Page 14 of 16

Mortgage Loan Information: (continued)

Notes:

characteristics, the Depositor instructed us to ignore differences that are due to standard postal abbreviations.

characteristics for each Mortgage Loan, the Depositor instructed us to ignore any prepayment premiums or other conditions related to partial release events or partial prepayments to cure certain trigger periods, as described in the applicable Source Document(s).

Exhibit 2 to Attachment A
Page 15 of 16

For the purpose of comparing the “Prepayment / Defeasance End Date” characteristic for each Mortgage Loan, the Depositor instructed us to use the day prior to the “Maturity Date,” as shown on the Preliminary Data File.

For the purpose of comparing the “Open Period Begin Date” characteristic for each Mortgage Loan, the Depositor instructed us to use the “Maturity Date,” as shown on the Preliminary Data File.

Exhibit 2 to Attachment A
Page 16 of 16

The Depositor instructed us to use “Yes” for the “Earthquake Insurance Required” characteristic if the “PML %” value on the Preliminary Data File is greater than or equal to 20%. If the “PML %” value on the Preliminary Data File is less than 20% or is “NAP” (as described in the preceding paragraph(s) of this Note), the Depositor instructed us to use “No” for the “Earthquake Insurance Required” characteristic.

We performed no procedures to determine the appropriateness, accuracy, completeness or reasonableness of the instructions, assumptions and methodologies provided by the Depositor that are described in the notes above.

Exhibit 3 to Attachment A

Provided Characteristics