# MAINLINE WEST MUNICIPAL SECURITIES LLC X-17A-5 (2026-03-05) — Broker-dealer annual report - Company: MAINLINE WEST MUNICIPAL SECURITIES LLC - Form: X-17A-5 - Filed: 2026-03-05 - Period: 2025-12-31 - Accession: 0001214659-26-002894 - CIK: 1440479 - File #: 8-67952 - Type: Broker-dealer - Material weakness: No - Auditor: Spicer Jeffries LLP - Contact: Anthony Caselli - Phone: 720-536-3396 - Email: acaselli@mainlinewest.net - Website: mainlinewest.net - Signed by: Anthony Caselli (Chief Financial Officer) Original filing: https://www.sec.gov/Archives/edgar/data/1440479/000121465926002894/mainlinewest_public.pdf --- {0}------------------------------------------------ #### **STATEMENT OF FINANCIAL CONDITION** **DECEMBER 31, 2025** The report is filed in accordance with Rule 17a-5(e)(3) under the Securities Exchange Act of 1934 as a **PUBLIC DOCUMENT**. {1}------------------------------------------------ UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 | OMB APPROVAL | | |---------------------------|--| | OMB Number: 3235-0123 | | | Expires: Nov. 30, 2026 | | | Estimated average burden | | | hours per response:
12 | | | SEC FILE NUMBER | | | 8-67952 | | # ANNUAL REPORTS FORM X-17A-5 PART III FACING PAGE Information Required Pursuant to Rules 17a-5, 17a-12, and 18a-7 under the Securities Exchange Act of 1934 AND ENDING\_12/31/2025 Filing for the period beginning 01/01/2025 MM/DD/YY MM/DD/YY A. REGISTRANT IDENTIFICATION NAME OF FIRM: Mainline West Municipal Securities LLC TYPE OF REGISTRANT (check all applicable boxes): | Broker-dealer | | Security-based swap dealer | | | Major security-based swap participant Check here if respondent is also an OTC derivatives dealer ADDRESS OF PRINCIPAL PLACE OF BUSINESS: (Do not use a P.O. box no.) | | | (No. and Street) | | | | |--------------------------------------------------------------------------------------------------|--------------|------------------------------------------------------------|-----------------|--------------------------------------------|--| | Denver | | CO | | 80211 | | | (City) | | (State) | | (Zip Code) | | | PERSON TO CONTACT WITH REGARD TO THIS FILING | | | | | | | Anthony Caselli | 720-536-3396 | | | acaselli@mainlinewest.net | | | (Name) | | (Area Code - Telephone Number) | (Email Address) | | | | | | B. ACCOUNTANT IDENTIFICATION | | | | | INDEPENDENT PUBLIC ACCOUNTANT whose reports are contained in this filing*
Spicer Jeffries LLP | | | | | | | | | (Name - if individual, state last, first, and middle name) | | | | | 4601 DTC Blvd, Suite 700 | | Denver | CO | 80237 | | | (Address) | | (City) | (State) | (Zip Code) | | | October 20, 2003 | | | 349 | | | | (Date of Registration with PCAOB)(if applicable) | | | | (PCAOB Registration Number, if applicable) | | | | | FOR OFFICIAL USE ONLY | | | | | | | | | | | \* Claims for exemption from the requirement that the annual reports of an independent public accountant must be supported by a statement of facts and circumstances relied on as the basis of the exemption. See 17 CFR 240.17a-5(e)(1)(ii), if applicable. Persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. {2}------------------------------------------------ #### OATH OR AFFIRMATION | I Anthony Caselli | swear (or affirm) that, to the best of my knowledge and belief, the | | |-------------------|---------------------------------------------------------------------|--| | | . | | financial report pertaining to the firm of Mainline West Municipal Securities LLC as of 12/31 2 025 , is true and correct. I further swear (or affirm) that neither the company nor any partner, officer, director, or equivalent person, as the case may be, has any proprietary interest in any account classified solely as that of a customer. ![](_page_2_Picture_4.jpeg) | Signature: | | |-------------------------|--| | Title: | | | Chief Financial Officer | | 8 arv Public #### This filing\*\* contains (check all applicable boxes): - (a) Statement of financial condition. - (b) Notes to consolidated statement of financial condition. - □ (c) Statement of income (loss) or, if there is other comprehensive in the period(s) presented, a statement of comprehensive income (as defined in § 210.1-02 of Regulation S-X). - O (d) Statement of cash flows. - [ (e) Statement of changes in stockholders' or partners' or sole proprietor's equity. - [ (f) Statement of changes in liabilities subordinated to claims of creditors. - [ (g) Notes to consolidated financial statements. - [ (h) Computation of net capital under 17 CFR 240.15c3-1 or 17 CFR 240.18a-1, as applicable. - □ (i) Computation of tangible net worth under 17 CFR 240.18a-2. - ロ (i) Computation of cangler not wordficustomer reserve requirements pursuant to Exhibit A to 17 CFR 240.15c3-3. - ロ ()/ Computation for determination of security-based swap reserve requirements pursuant to Exhibit B to 17 CFR 240.15c3-3 or Exhibit A to 17 CFR 240.18a-4, as applicable. - [ (I) Computation for Determination of PAB Requirements under Exhibit A to § 240.15c3-3. - | | Configures ion relating to possession or control requirements for customers under 17 CFR 240.15c3-3. - ロ (n) Information relating to possession or control requirements for security-based swap customers under 17 CFR - 240.15c3-3(p)(2) or 17 CFR 240.18a-4, as applicable. - 240.250.2012.01 17 CF C R 2 R 2 R 2 R 2 R 2 R 2 Report with computation of net capital of the Copital of the Market (0) Reconclined on 17 CFR 240.18a-1, or 17 CFR 240.18a-2, as applicable, and the reserve requirements under 17 worth under 17 CFR 240.186-4, as applicable, if material differences exist, or a statement that no material differences exist. - □ (p) Summary of financial data for subsidiaries not consolidated in the statement of financial condition. - ー (q) Sunmary of mancial acturer acter for basiatel 17 CFR 240.17a-12, or 17 CFR 240.18a-7, as applicable. (q) Oath or affirmation in accordance with 17 CFR 240.17a-5, 17 - [ (r) Compliance report in accordance with 17 CFR 240.17a-5 or 17 CFR 240.18a-7, as applicable. - [ (s) Exemption report in accordance with 17 CFR 240.17a-5 or 17 CFR 240.18a-7, as applicable. - = (t) Independent public accountant's report based on an examination of the statement of financial condition. - (\1) hidependent public accountant's report based on an examination of the financial statements under 17 CFR 240.17a-5, 17 CFR 240.18a-7, or 17 CFR 240.17a-12, as applicable. - CFR 240.278-3, 17 Ch 240.2017, 8 report based on an examination of certain statements in the compliance report under 17 CFR 240.17a-5 or 17 CFR 240.18a-7, as applicable. - Cr CFR 240.178-5 of 17 CFR 210.17 of the exemption report under 17 CFR 240.17a-5 or 17 CFR 240.18a-7, as applicable. - CH 240.15c3 research reports on applying agreed-upon procedures, in accordance with 17 CFR 240.17a-12, as applicable. - as applicable. [y] Report describing any material inadequacies found to exist or found to have existed since the date of the previous audit, or a statement that no material inadequacies exist, under 17 CFR 240.17a-12(k). - □ (z) Other: - \*\*To request confidential treatment of certain portions of this filing, see 17 CFR 240.17a-5(e)(3) or 17 CFR 240.18a-7(d)(2), as applicable. {3}------------------------------------------------ #### **TABLE OF CONTENTS** | | Page
(s) | |---------------------------------------------------------|-------------| | Report of Independent Registered Public Accounting Firm | 3 | | Statement of Financial Condition | 4 | | Notes to Financial Statements | 5 –
10 | {4}------------------------------------------------ ![](_page_4_Picture_0.jpeg) ## **REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM** To the Board of Directors and Members of Mainline West Municipal Securities LLC ### **Opinion on the Financial Statements** We have audited the accompanying statement of financial condition of Mainline West Municipal Securities LLC (the "Company") as of December 31, 2025, and the related notes (collectively referred to as the "financial statements"). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 in conformity with accounting principles generally accepted in the United States of America. ## **Basis for Opinion** These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company's financial statements based on our audit. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audit included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audit also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audit provides a reasonable basis for our opinion. We have served as Mainline West Municipal Securities LLC's auditor since 2025. Denver, Colorado February 24, 2026 {5}------------------------------------------------ ### **STATEMENT OF FINANCIAL CONDITION DECEMBER 31, 2025** #### **ASSETS** | Cash | \$
229,600 | |-------------------------------------------------------------------|-----------------| | Cash
and
cash
equivalents
at clearing
broker | 988 | | Securities
owned,
at fair
value
(Notes
1 and
3) | 2,140,254 | | Deposit
with
clearing
broker | 106,683 | | Total assets | \$
2,477,525 | | LIABILITIES AND MEMBERS' EQUITY | | | LIABILITIES: | | | Due to clearing
broker | \$
54,812 | | Due to affiliates
(Note
4) | 447,245 | | Accounts payable
and
accrued
expenses | 19,317 | | Total liabilities | 521,374 | | COMMITMENTS AND CONTINGENCIES (Notes
4, 5 and
6) | | | MEMBERS' EQUITY (Notes
1 and
2) | 1,956,151 | | Total liabilities and members' equity | \$
2,477,525 | {6}------------------------------------------------ ## **NOTES TO STATEMENT OF FINANCIAL CONDITION** ## *NOTE 1 - ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES* ### *Organization and business* Mainline West Municipal Securities LLC (the "Company") was formed on February 20, 2008, pursuant to the laws of the State of Delaware. The Company is a broker-dealer registered with the Securities and Exchange Commission and the Financial Industry Regulatory Authority, Inc. The Company's brokerdealer license became effective December 3, 2008. The Company is engaged in the general retail securities business and deals primarily in municipal securities which it buys and sells on behalf of its customers on a fully disclosed basis, and also for its own account in its proprietary trading activities. ## *Clearing Agreement* The Company, under Rule 15c3-3(k)(2)(ii), is exempt from the reserve and possession or control requirements of Rule 15c3-3 of the Securities and Exchange Commission. The Company does not carry or clear customer accounts. Accordingly, all customer transactions are executed and cleared on behalf of the Company by its clearing broker on a fully disclosed basis. The Company's agreement with its clearing broker provides that as clearing broker, that firm will make and keep such records of the transactions effected and cleared in the customer accounts as are customarily made and kept by a clearing broker pursuant to the requirements of Rules 17a-3 and 17a-4 of the Securities and Exchange Act of 1934, as amended (the "Act"). It also performs all services customarily incident thereon, including the preparation and distribution of customer's confirmations and statements and maintenance margin requirements under the Act and the rules of the Self Regulatory Organizations of which the Company is a member. ## *Securities Valuation and Revenue Recognition* The Company records proprietary transactions, trading profits and related expenses on a trade-date basis. The Company values its securities in accordance with Accounting Standards Codification 820 - Fair Value Measurements ("ASC 820"). Under ASC 820, fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (i.e., the "exit price") in an orderly transaction between market participants at the measurement date. ASC 820 establishes a fair value hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. Observable inputs are those that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs reflect the Company's assumption about the inputs market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. The fair value hierarchy is categorized into three levels based on the inputs as follows: {7}------------------------------------------------ #### **NOTES TO STATEMENT OF FINANCIAL CONDITION** *(continued)* ## *NOTE 1 - ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (continued)* #### *Securities Valuation and Revenue Recognition (concluded)* Level 1 - Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access. Valuation adjustments are not applied to Level 1 securities. Since valuations are based on quoted prices that are readily and regularly available in an active market, valuation of these securities does not entail a significant degree of judgment. Level 2 - Valuations based on quoted prices in markets that are not active or for which all significant inputs are observable, either directly or indirectly. Level 3 - Valuations based on inputs that are unobservable and significant to the overall fair value measurement. The availability of valuation techniques and observable inputs can vary from security to security and is affected by a wide variety of factors, including the type of security, whether the security is new and not yet established in the marketplace, and other characteristics particular to the transaction. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Those estimated values do not necessarily represent the amounts that may be ultimately realized due to the occurrence of future circumstances that cannot be reasonably determined. Because of the inherent uncertainty of valuation, those estimated values may be materially higher or lower than the values that would have been used had a ready market for the securities existed. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for securities categorized in Level 3. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the level in the fair value hierarchy within which the fair value measurement falls in its entirety is determined by the lowest level input that is significant to the fair value measurement. Fair value is a market-based measure considered from the perspective of a market participant rather than an entity-specific measure. Therefore, even when market assumptions are not readily available, the Company's own assumptions are set to reflect those that market participants would use in pricing the asset or liability at the measurement date. The Company uses prices and inputs that are current as of the measurement date, including during periods of market dislocation. In periods of market dislocation, the observability of prices and inputs may be reduced for many securities. This condition could cause a security to be reclassified to a lower level within the fair value hierarchy. The fair value of municipal bonds is estimated using recently executed transactions and market price quotations. Municipal bonds are generally categorized in Level 2 of the fair value hierarchy (see Note 3). The Company accounts for interest income on the accrual basis. {8}------------------------------------------------ ### **NOTES TO STATEMENT OF FINANCIAL CONDITION** *(continued)* # *NOTE 1 - ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (continued)* ## *Estimates* The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting year. Actual results could differ from those estimates. ## *Income Taxes* The Company is recognized as a limited liability company by the Internal Revenue Service. Accordingly, the Company's members are liable for federal and state income taxes on their respective tax returns. Although the Company is not a taxable entity, it must file income tax returns and take tax positions that are passed through to its members. The Company is required to determine whether a tax position is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any tax related appeals or litigation processes, based on the technical merits of the position. The Company files an income tax return in the U.S. federal jurisdiction and files and income tax return in the state of Colorado. The Company is not subject to income tax return examinations by major taxing authorities for years before 2022. No interest expense or penalties have been recognized as of and for the year ended December 31, 2025. # *Cash Equivalents* For purposes of the statement of cash flows, the Company considers all money market accounts held at their clearing broker to be cash equivalents. # *Profit and Loss Allocations* Profits and losses from operations are allocated to members based on the Operating Agreement of the Company. The Operating Agreement of the Company generally provides for this allocation to be made in proportion to the number of units held by the respective members at the end of each calendar month. # *Futures Contracts* The Company is subject to equity and commodity price risk, interest rate risk, and foreign currency exchange rate risk in the normal course of pursuing its investment objectives. The Company may use futures contracts to gain exposure to, or hedge against, changes in the value of equities and commodities, interest rates or foreign currencies. A futures contract represents a commitment for the future purchase or sale of an asset at a specified price on a specified date. {9}------------------------------------------------ #### **NOTES TO STATEMENT OF FINANCIAL CONDITION** *(continued)* ### *NOTE 1 - ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (concluded)* #### *Segment Reporting* The Company has identified its Chief Financial Officer as the chief operating decision maker ("CODM"), who uses net income to evaluate the results of the business, predominantly in the forecasting process, to manage the Company. Additionally, the CODM uses excess net capital (see Note 2), which is not a measure of profit and loss, to make operational decisions while maintaining capital adequacy, such as whether to reinvest profits or pay distributions. The Company's operations constitute a single operating segment and therefore, a single reportable segment, because the CODM manages the business activities using information of the Company as a whole. The accounting policies used to measure the profit and loss of the segment are the same as those described in the summary of significant accounting policies. ### *NOTE 2 - NET CAPITAL REQUIREMENTS* Pursuant to the net capital provisions of Rule 15c3-1 of the Securities Exchange Act of 1934, the Company is required to maintain a minimum net capital, as defined under such provisions. At December 31, 2025, the Company had net capital and net capital requirements of \$1,796,106 and \$100,000, respectively. The Company's net capital ratio (aggregate indebtedness to net capital) was 0.26 to 1. According to Rule 15c3-1, the Company's net capital ratio shall not exceed 15 to 1. ### *NOTE 3 - FAIR VALUE MEASUREMENTS* The Company's assets recorded at fair value have been categorized based upon a fair value hierarchy in accordance with ASC 820. See Note 1 for a discussion of the Company's policies. The following table presents information about the Company's assets measured at fair value as of December 31, 2025: | | Quoted Prices in
Active Markets
for Identical Assets
(Level 1) | Significant
Other Observable
Inputs
(Level 2) | Significant
Unobservable
Inputs
(Level 3) | Balances as of
December 31, 2025 | | |-----------------|-------------------------------------------------------------------------|--------------------------------------------------------|----------------------------------------------------|-------------------------------------|--| | Assets: | \$ | \$ | \$ | \$ | | | Municipal bonds | - | 2,140,254 | - | 2,140,254 | | The Company did not have any significant transfers between levels during the year ended December 31, 2025. {10}------------------------------------------------ ## **NOTES TO STATEMENT OF FINANCIAL CONDITION** *(continued)* # *NOTE 4 - RELATED PARTY TRANSACTIONS* The Company shares offices with an entity affiliated through common ownership (the "Affiliate"). The Company has an expense sharing agreement (the "Agreement") with the Affiliate. Under the Agreement, the Company and the Affiliate share common expenses such as rent, compensation, equipment and other operating expenses based on efforts expended for each entity. As of December 31, 2025, the Company had a payable to the Affiliate in the amount of \$447,245 related to net expenses paid by the Affiliate on behalf of the Company. The Company receives \$133,333 per annum for execution services performed for the Affiliate. # *NOTE 5 - COMMITMENTS* Mainline West Municipal Securities LLC pays \$2,000 per month for rent to an affiliate company, as part of an expense sharing agreement. There is no formal commitment or agreement in place requiring the Company to pay. Total rental expense is included in occupancy costs and totaled \$24,000 for the year ended December 31, 2025. # *NOTE 6 - FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES* In the normal course of business, the Company's activities through its clearing broker involve the execution, settlement and financing of various customer securities transactions. These activities may expose the Company to off-balance sheet risk. In the event a customer fails to satisfy its obligations, the Company may be required to purchase or sell financial instruments at prevailing market prices in order to fulfill the customer's obligations. In the Company's trading activities, the Company purchases and sells securities for its own account and may incur losses if the market value of these securities decline subsequent to December 31, 2025. Further, the Company trades on margin and may be required to post additional collateral should the market values of the Company's inventory positions decline. In addition, the Company bears the risk of financial failure by its clearing broker. If the clearing broker should cease doing business, the Company's receivable and deposit from this clearing broker could be subject to forfeiture. The Company also maintains its cash balance in a financial institution, which at times may exceed federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to any significant credit risk. The Company's financial instruments, including cash, cash and cash equivalents at clearing broker, deposit with clearing broker, due to clearing broker, due to affiliates, and accounts payable and accrued expenses are carried at amounts which approximate fair value. Securities owned are valued as described in Note 1. {11}------------------------------------------------ #### **NOTES TO STATEMENT OF FINANCIAL CONDITION** *(concluded)* #### *NOTE 7 - SUBSEQUENT EVENTS* The Company has performed an evaluation of subsequent events through the date the financial statements were issued. The evaluation did not result in any events that required disclosure. Source: SEC EDGAR via Adviser Search (https://search.stillhousedata.com). Agents: see https://search.stillhousedata.com/llms.txt.