UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington D.C. 20549

FORM 10-D

ASSET BACKED ISSUER
DISTRIBUTION REPORT PURSUANT TO SECTION 13 OR 15(d) OF
THE SECURITIES EXCHANGE ACT OF 1934

For the monthly distribution period from: January 17, 2026 to February 18, 2026

Commission File Number of issuing entity: 333-199921-01

Central Index Key Number of issuing entity: 0001634172

CSAIL 2015-C1 Commercial Mortgage Trust
(Exact name of issuing entity as specified in its charter)

Commission File Number of depositor: 333-199921

Central Index Key Number of depositor: 0000802106

Credit Suisse First Boston Mortgage Securities Corp.
(Exact name of depositor as specified in its charter)

Central Index Key Number of sponsor (if applicable): 0001628601

Column Financial, Inc.
(Exact name of sponsor as specified in its charter)

Central Index Key Number of sponsor (if applicable): 0001576832

MC-Five Mile Commercial Mortgage Finance LLC
(Exact name of sponsor as specified in its charter)

Central Index Key Number of sponsor (if applicable): 0001505494

The Bancorp Bank, National Association (formerly known as The Bancorp Bank)
(Exact name of sponsor as specified in its charter)

Central Index Key Number of sponsor (if applicable): 0001632269

Benefit Street Partners CRE Finance LLC (formerly known as BSPCC Lender L.L.C.)
(Exact name of sponsor as specified in its charter)

Nader Attalla (212) 325-4217
(Name and telephone number, including area code, of the person to contact in connection with this filing)

New York
(State or other jurisdiction of incorporation or organization of the issuing entity)

38-3955488
38-3955489
(I.R.S. Employer Identification No.)

c/o Computershare Trust Company, N.A., as agent for
Wells Fargo Bank, National Association
9062 Old Annapolis Road
Columbia, MD 21045
(Address of principal executive offices of the issuing entity) (Zip Code)

(667) 786-1992
(Telephone number, including area code)

Not Applicable
(Former name, former address, if changed since last report)

Registered/reporting pursuant to (check one)

Title of Class	Section 12(b)	Section 12(g)	Section 15(d)	Name of Exchange (If Section 12(b))
A-1			X
A-2			X
A-3			X
A-4			X
A-SB			X
A-S			X
B			X
C			X
X-A			X
X-B			X

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes X No

Part I - DISTRIBUTION INFORMATION

Item 1. Distribution and Pool Performance Information.

On February 18, 2026 a distribution was made to holders of the certificates issued by CSAIL 2015-C1 Commercial Mortgage Trust.

The distribution report is attached as an Exhibit to this Form 10-D, please see Item 10(b), Exhibit 99.1 for the related information.

The following table presents the loss information for the trust assets for the CSAIL 2015-C1 Commercial Mortgage Trust in accordance with Item 1100(b) as required by Item 1121(a)(9) of Regulation AB:

Loss Information as reported on February 18, 2026

Number of Delinquencies 30+ days	% of Delinquencies 30+ days by Pool Balance	Number of Loans/REOs with Losses	Average Net Loss
4	45.02%	6	$6,309,184.62

No assets securitized by Credit Suisse First Boston Mortgage Securities Corp. (the "Depositor") and held by CSAIL 2015-C1 Commercial Mortgage Trust were the subject of a demand to repurchase for breach of the representations and warranties contained in the underlying transaction documents during the distribution period from January 17, 2026 to February 18, 2026.

The Depositor has filed a Form ABS-15G pursuant to Rule 15Ga-1 under the Securities Exchange Act of 1934 on February 11, 2026. The CIK number of the Depositor is 0000802106.

Column Financial, Inc. ("Column"), one of the sponsors, has filed a Form ABS-15G pursuant to Rule 15Ga-1 under the Securities Exchange Act of 1934 on February 11, 2026. The CIK number of Column is 0001628601.

MC-Five Mile Commercial Mortgage Finance LLC ("MC-Five Mile"), one of the sponsors, has filed a Form ABS-15G pursuant to Rule 15Ga-1 under the Securities Exchange Act of 1934 on February 16, 2021. The CIK number of MC-Five Mile is 0001576832.

The Bancorp Bank, National Association (formerly known as The Bancorp Bank) ("Bancorp"), one of the sponsors, has filed a Form ABS-15G pursuant to Rule 15Ga-1 under the Securities Exchange Act of 1934 on February 10, 2026. The CIK number of Bancorp is 0001505494.

Benefit Street Partners CRE Finance LLC (formerly known as BSPCC Lender L.L.C.) ("BSPCF"), one of the sponsors, has filed a Form ABS-15G pursuant to Rule 15Ga-1 under the Securities Exchange Act of 1934 on February 13, 2026. The CIK number of BSPCF is 0001632269.

Part II - OTHER INFORMATION

Item 2. Legal Proceedings.

Disclosure from CWCapital Asset Management LLC, as special servicer:

From time to time, CWCapital Asset Management LLC, a Delaware limited liability company (“CWCAM”), is a party to lawsuits and other legal proceedings as part of its duties as a special servicer (e.g., enforcement of loan obligations) and/or arising in the ordinary course of business. Other than as set forth in the following paragraphs, there are currently no legal proceedings pending, and no legal proceedings known to be contemplated by governmental authorities, against CWCAM or of which any of its property is the subject, that are material to the certificateholders.

On December 1, 2017, a complaint against CWCAM and others was filed in the United States District Court for the Southern District of New York styled as CWCapital Cobalt Vr Ltd. v. CWCapital Investments LLC, et al., No. 17-cv-9463 (the “Original Complaint”). The gravamen of the Original Complaint alleged breaches of a contract and fiduciary duties by CWCAM’s affiliate, CWCapital Investments LLC in its capacity as collateral manager for the collateralized debt obligation transaction involving CWCapital Cobalt Vr, Ltd. In total, there are 14 counts pled in the Original Complaint. Of those 14, 5 claims were asserted against CWCAM for aiding and abetting breach of fiduciary duty, conversion and unjust enrichment. On May 23, 2018, the Original Complaint was dismissed for lack of subject matter jurisdiction. On June 28, 2018, CWCapital Cobalt Vr Ltd. filed a substantially similar complaint in the Supreme Court of the State of New York, County of New York styled as CWCapital Cobalt Vr Ltd. v. CWCapital Investments LLC, et al., Index No. 653277/2018 (the “New Complaint”). The gravamen of the New Complaint is the same as the previous complaint filed in the United State District Court for the Southern District of New York. In total there are 16 counts pled in the New Complaint. Of those 16 counts, 5 claims were asserted against CWCAM for aiding and abetting breach of fiduciary duty, conversion and unjust enrichment, 1 count seeks a declaratory judgement that the plaintiff has the right to enforce the contracts in question and 1 count seeks an injunction requiring the defendants to recognize the plaintiff as the directing holder for the trusts in question. On January 11, 2019, the plaintiff dismissed with prejudice the declaratory judgment and injunction counts. The New Complaint and related summons was not served on the defendants until July 13, 2018 and July 16, 2018. The plaintiff’s motion for a preliminary injunction was denied by the court on July 31, 2018. On August 3, 2018, the defendants, including CWCAM, filed a motion to dismiss the New Complaint in its entirety. On August 20, 2019, the court entered an order granting defendants’ motion almost in its entirety, dismissing 11 of the 16 counts and partially dismissing 2 additional counts. Of the remaining counts, 2 are asserted against CWCAM for aiding and abetting breach of fiduciary duty and unjust enrichment. On September 19, 2019, CWCapital Cobalt Vr Ltd. filed a notice of appeal relating to the August 20, 2019 dismissal order and on September 26, 2019, filed an amended complaint against CWCI and CWCAM attempting to address deficiencies relating to certain of the claims dismissed by the August, 20, 2019 order. CWCI and CWCAM filed its Motion to Dismiss the amended complaint on October 28, 2019. The court heard argument on the Motion to Dismiss the amended complaint on January 22, 2020 and on October 23, 2020, the court granted the motion dismissing the amended claims. On November 30, 2020, CWCapital Cobalt Vr Ltd filed a notice of appeal relating to the October 23, 2020 dismissal order. On April 27, 2021, the First Department affirmed the dismissal as to claims against CWCAM that were part of the August 20, 2019 dismissal, but reversed the dismissal of two counts for breach of the Collateral Management Agreement against CWCI. CWCI sought leave to file an appeal of the decision. The plaintiff also sought leave to appeal the dismissal of the claims against CWCAM. Both requests for leave were denied by the First Department. On May 15, 2020, CWCI and CWCAM filed a motion to renew its motion to dismiss as to 4 of the remaining counts (including the remaining two counts against CWCAM for aiding and abetting breach of fiduciary duty and unjust enrichment), based on a decision entered by Judge Failla in a trust instruction proceeding in the US District Court for the Southern District of New York awarding summary judgment in favor of CWCAM. On September 7, 2021, the court denied the motion to renew. CWCI and CWCAM filed a notice of appeal, which they perfected by the filing of their opening brief on July 1, 2022. On November 15, 2022, the First Department affirmed the court’s denial of the motion to renew. On October 1, 2021, CWCI and CWCAM moved to reargue the denial of the motion to renew (or alternatively, the motion to dismiss) with respect to certain of Cobalt’s claims, including the remaining 2 claims against CWCAM, based on the First Department’s April 27, 2021 decision. On March 24, 2022, the court denied the relief sought in the motion to reargue. CWCI and CWCAM appealed the court’s decision on the motion to reargue and filed their opening brief on July 11, 2022. The appeal was dismissed as being non-appealable on August 30, 2022. Discovery (both fact and expert) concluded on March 1, 2024. CWCAM and CWCI filed a motion for summary judgment on March 29, 2024, seeking dismissal of all the claims in their entirety. On that same date, the plaintiff cross moved for summary judgment on one of the claims asserted against only CWCI. Oral argument on the parties’ summary judgment motions were heard on October 22, 2024. . On January 13, 2026, the court denied plaintiff’s motion for summary judgment and granted, in part, and denied, in part, the motion filed by CWCI and CWCAM. Specifically, the court dismissed the remaining two counts against CWCAM for aiding and abetting breach of fiduciary duty and unjust enrichment. With respect to CWCI, the court dismissed two counts against CWCI in their entirety and dismissed portions of one count against CWCI. The only three counts that survived and remain in the case are against CWCI. The court severed the dismissed claims from the surviving claims. On January 22, 2026, CWCI and CWCAM submitted an order to the court, requesting that it direct the clerk’s office to enter judgment on the dismissed claims and that CWCAM be dismissed as a defendant from the action. CWCAM believes that it has performed its obligations under the related pooling and servicing agreements in good faith.

On January 13, 2025, in the Supreme Court of the State of New York, ROC Debt Strategies II Bond Investments LLC (“Bridge Investment Group or “Bridge”), as Directing Certificateholder (“DCH”) filed suit against CWCapital Asset Management LLC (“CWCAM”), alleging breach of the subject Pooling and Servicing Agreement (“PSA”) and violation of the Servicing Standard while acting as special servicer for the FREMF 2016-KS06 pool. It is alleged that CWCAM was negligent in the servicing of a portfolio of 9 loans (the “Ranger Portfolio”) that were in special servicing starting in 2022. The suit demands unspecified compensatory damages and a Declaratory Judgment that CWCAM is not entitled to indemnification or payment for expenses from the Trust under the PSA. CWCAM disagrees vehemently with these allegations and a Motion to Dismiss was filed by CWCAM on March 14, 2025. The motion has been fully briefed and a hearing was held on August 25, 2025 While that motion was pending, the parties reached a business resolution and by stipulation the lawsuit was dismissed with prejudice on January 22, 2026.

Item 10. Exhibits.

(a) The following is a list of documents filed as part of this Report on Form 10-D:

(99.1) Monthly report distributed to holders of the certificates issued by CSAIL 2015-C1 Commercial Mortgage Trust, relating to the February 18, 2026 distribution.

(b) The exhibits required to be filed by the Registrant pursuant to this Form are listed above.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Credit Suisse First Boston Mortgage Securities Corp.
(Depositor)

/s/ Dmitriy Kogan
Dmitriy Kogan, Authorized Signatory

Date: February 26, 2026

/s/ Russell Moy
Russell Moy, Authorized Signatory

CSAIL 2015-C1 Commercial Mortgage Trust 10-D