Exhibit 10.5

CONVERTIBLE PROMISSORY NOTE

FOR VALUE RECEIVED, Cardiff Lexington Corporation, a Nevada corporation, its successors and assigns (the “Company”), hereby promises to pay to Greentree Financial Group Inc., a Florida corporation, or its successors or assigns (the “Holder”), in immediately available funds, the total principal sum of up to Eighty Thousand Dollars ($80,000.00) with a 10% original issuance discount, in accordance with the terms of this Convertible Promissory Note (this “Note”). The principal hereof and any unpaid accrued interest thereon shall be due and payable upon demand by Holder in accordance with Section 1, below (unless such payment date is accelerated as provided in Section 8 hereof). Payment of all amounts due hereunder shall be made at the address of the Holder provided for in Section 9 hereof, or as otherwise directed by Holder.

1.1 Interest. Interest on the Note shall commence accruing from the date funds have been advanced and shall continue to accrue until all unpaid principal and interest is paid in full. Interest shall be computed on the basis of a 360-day year and twelve 30-day months pursuant to the interest rates as defined in the Note, and shall be payable in arrears for on the first calendar day of each calendar quarter (each, an “Interest Date”) with the first Interest Date being March 1, 2026. Interest shall be payable on each Interest Date, to the record holder of this Note on the applicable Interest Date, in shares of Common Stock (“Interest Shares”) so long as there has been no Equity Conditions Failure; provided however, that the Company may, at its option following notice to the Lender, pay Interest on any Interest Date in cash (“Cash Interest”) or in a combination of Cash Interest and Interest Shares.

1.2       Interest Rate. As of any date of determination, twelve percent (12%) per annum; provided, that if such Interest is being paid in shares of Common Stock hereunder, such Interest shall recalculated in connection with such issuance of shares of Common Stock at a deemed rate of fifteen percent (15%) per annum.

1.3 Repayment upon Qualified Financing. In the event that the Company consummates any kinds of financing of at least $2.5 million while the Note is outstanding (a “Qualified Financing”), the Company agrees to apply proceeds from its Qualified Financing to repayment of any outstanding balance of this Note, upon the request by the Holder, until it has been paid in full.

4.1       Conversion Right. The Holder shall have the right, at any time on or after the Issuance Date prior to the Maturity Date to convert all or any portion of the then outstanding and unpaid Principal Amount and interest (including any Default Interest) into fully paid and non-assessable shares of Common Stock, as such Common Stock exists on the Issue Date, or any shares of capital stock or other securities of the Company into which such Common Stock shall hereafter be changed or reclassified, at the Conversion Price (as defined below) determined as provided herein (a “Conversion”). The Company shall not issue any fraction of a share of Common Stock upon any conversion. If the issuance would result in the issuance of a fraction of a share of Common Stock, the Company shall round such fraction of a share of Common Stock up to the nearest whole share. The Company shall pay any and all transfer, stamp, issuance and similar taxes, costs and expenses (including, without limitation, fees and expenses of the Transfer Agent) that may be payable with respect to the issuance and delivery of Common Stock upon conversion of any Conversion Amount; provided, however, that in no event shall the Holder be entitled to convert any portion of this Note in excess of that portion of this Note upon conversion of which the sum of (1) the number of shares of Common Stock beneficially owned by the Holder and its affiliates (other than shares of Common Stock which may be deemed beneficially owned through the ownership of the unconverted portion of this Note or the unexercised or unconverted portion of any other security of the Company subject to a limitation on conversion or exercise analogous to the limitations contained herein) and (2) the number of Conversion Shares issuable upon the conversion of the portion of this Note with respect to which the determination of this proviso is being made, would result in beneficial ownership by the Holder and its affiliates of more than 4.9% of the then outstanding shares of Common Stock. For purposes of the proviso set forth in the immediately preceding sentence, beneficial ownership shall be determined in accordance with Section 13(d) of the Securities Exchange Act of 1934, as amended (the “1934 Act”), and Regulations 13D-G thereunder, except as otherwise provided in clause (1) of such proviso, provided, however, that the limitations on conversion may be waived (up to 9.99%) by the Holder upon, at the election of the Holder, not less than 61 days’ prior notice to the Company, and the provisions of the conversion limitation shall continue to apply until such 61st day (or such later date, as determined by the Holder, as may be specified in such notice of waiver). The number of Conversion Shares to be issued upon each conversion of this Note shall be determined by dividing the Conversion Amount (as defined below) by the applicable Conversion Price then in effect on the date specified in the notice of conversion, in the form attached hereto as Exhibit B (the “Notice of Conversion”), delivered to the Company; provided that the Notice of Conversion is submitted by facsimile or e-mail (or by other means resulting in, or reasonably expected to result in, notice) to the Company before 11:59 p.m., New York, New York time on such conversion date (the “Conversion Date”).

4.2 Conversion Rate. The number of shares of Common Stock issuable upon conversion of any Conversion Amount pursuant to Section 4.1 shall be determined by dividing (x) such Conversion Amount by (y) the Conversion Price (or, with respect to the conversion of any Make-Whole Amount, the Alternate Conversion Price as of the applicable Conversion Date) (the “Conversion Rate”).

4.3 Conversion Amount. With respect to any conversion of this Note, Conversion Amount means the sum of (A) the portion of the Principal of this Note to be converted, redeemed or otherwise with respect to which this determination is being made, (B) accrued and unpaid Interest with respect to such Principal of this Note, (C) the Make-Whole Amount, if any, (D) accrued and unpaid Late Charges with respect to such Principal of this Note, Make-Whole Amount and Interest, (E) any other unpaid amounts pursuant to the Transaction Documents (including, without limitation, conversion cost as set forth in Section 5), if any, and (F) at the Holder’s option, Default Interest, if any, on the amounts referred to in the immediately preceding clauses (A) and/or (B).

4.4 Make-Whole Amount means, as of any given date and as applicable, in connection with any conversion, redemption or other repayment hereunder, an amount equal to the amount of additional Interest that would accrue under this Note at the Interest Rate then in effect assuming for calculation purposes that the outstanding Principal of this Note as of the Closing Date remained outstanding through and including the Maturity Date.

4.5 Conversion Price means, as of any Conversion Date or other date of determination, $0.275, subject to adjustment as provided herein. The Conversion Price shall be subject to adjustment in the event of a reverse or forward split.

4.6 Conversion Price Resets. If on any six month anniversary of the Effective Date (each, a “Reset Date”), the Conversion Price then in effect is greater than the Closing Bid Price of the Common Stock as of such applicable Reset Date (each, a “Reset Price”), immediately after the close of the Principal Market on such applicable Reset Date the Conversion Price shall automatically lower to such applicable Reset Price.

4.7 Alternate Conversion Price means, with respect to any Alternate Conversion that price which shall be the lowest of (i) the applicable Conversion Price as in effect on the applicable Conversion Date of the applicable Alternate Conversion, (ii) 90% of the lowest VWAP of the Common Stock during the five (5) consecutive Trading Day period ending and including the Trading Day immediately preceding the delivery or deemed delivery of the applicable Conversion Notice (such period, the “Alternate Conversion Measuring Period”). All such determinations to be appropriately adjusted for any stock dividend, stock split, stock combination, reclassification or similar transaction that proportionately decreases or increases the Common Stock during such Alternate Conversion Measuring Period.

4.8       Conversion Price During Major Announcements. Notwithstanding anything contained in Section 4.5 to the contrary, in the event the Company (i) makes a public announcement that it intends to be acquired by, consolidate or merge with any other corporation or entity (other than a merger in which the Company is the surviving or continuing corporation and its capital stock is unchanged) or sell or transfer all or substantially all of the assets of the Company; or (ii) any person, group or entity (including the Company) publicly announces a tender offer to purchase 50% or more of the Common Stock (or any other takeover scheme) (any such transaction referred to in clause (i) or (ii) being referred to herein as a “Change in Control” and the date of the announcement referred to in clause (i) or (ii) is being referred to herein as the “Announcement Date”), then the Conversion Price shall, effective upon the Announcement Date and continuing through the Adjusted Conversion Price Termination Date (as defined below), be equal to the lower of (x) the Conversion Price and (y) a 25% discount to the Acquisition Price (as defined below). From and after the Adjusted Conversion Price Termination Date, the Conversion Price shall be determined as set forth in Section 4.5. For purposes hereof, “Adjusted Conversion Price Termination Date” shall mean, with respect to any proposed Change in Control for which a public announcement as contemplated by this Section 4.7 has been made, the date upon which the Company (in the case of clause (i) above) or the person, group or entity (in the case of clause (ii) above) consummates or publicly announces the termination or abandonment of the proposed Change in Control which caused this Section 4.7 to become operative. For purposes hereof, “Acquisition Price” shall mean a price per share of Common Stock derived by dividing (x) the total consideration (in cash, equity, earn-out or similar payments or otherwise) paid or to be paid to the Company or its shareholders in the Change in Control transaction by (y) the number of authorized shares of Common Stock outstanding as of the business day prior to the Announcement Date.

4.9       Authorized and Reserved Shares. The Company covenants that at all times until the Note is satisfied in full, the Company will reserve from its authorized and unissued Common Stock a sufficient number of shares, free from preemptive rights, to provide for the issuance of a number of Conversion Shares equal to the number of Conversion Shares issuable upon the full conversion of this Note (assuming no payment of Principal Amount or interest) as of any issue date (taking into consideration any adjustments to the Conversion Price pursuant to Section 4.5 hereof or otherwise) (the “Reserved Amount”). In the event that the Company shall be unable to reserve the entirety of the Reserved Amount (the “Reserve Amount Failure”), the Company shall promptly take all actions necessary to increase its authorized share capital to accommodate the Reserved Amount (the “Authorized Share Increase”), including without limitation, all board of directors actions and approvals and promptly (but no less than 60 days following the calling and holding a special meeting of its shareholders no more than 60 days following the Reserve Amount Failure to seek approval of the Authorized Share Increase via the solicitation of proxies. Notwithstanding the foregoing, in no event shall the Reserved Amount be lower than the initial Reserved Amount, regardless of any prior conversions. The Company represents that upon issuance, the Conversion Shares will be duly and validly issued, fully paid and non-assessable. In addition, if the Company shall issue any securities or make any change to its capital structure which would change the number of Conversion Shares into which this Note shall be convertible at the then current Conversion Price, the Company shall at the same time make proper provision so that thereafter there shall be a sufficient number of shares of Common Stock authorized and reserved, free from preemptive rights, for conversion of this Note. The Company (i) acknowledges that it has irrevocably instructed its transfer agent to issue certificates for the Conversion Shares or instructions to have the Conversion Shares issued, and (ii) agrees that its issuance of this Note shall constitute full authority to its officers and agents who are charged with the duty of executing stock certificates or cause the Company to electronically issue shares of Common Stock to execute and issue the necessary certificates for the Conversion Shares or cause the Conversion Shares to be issued in accordance with the terms and conditions of this Note.

If, at any time the Company does not maintain the Reserved Amount it will be considered an Event of Default under this Note.

(a)       In case the Company shall at any time prior to the conversion of the Note, or the maturity of the Note, whichever occurs later, effect a recapitalization or reclassification of such character that its Common Stock shall be changed into or become exchangeable for a larger number of shares, then, upon the effective date thereof, the number of shares of Common Stock that the Holder of this Note shall be entitled to convert hereof shall be increased in direct proportion to the increase in such number of shares of Common Stock by reason of such recapitalization or reclassification, and the Conversion Price of such recapitalized or reclassified Common Stock shall, in the case of an increase in the number of shares, be proportionately decreased.

(b)       In case the Company shall at any time prior to the conversion of the Note, or the maturity of the Note, whichever occurs later, grant, issue or sell any Common Stock, options to purchase Common Stock, securities convertible into Common Stock or rights relating to Common Stock (the “Purchase Rights”) to any person, entity, association, or other organization other than the Holder, at a price per share less than the Conversion Price defined in Section 4.5 (a “Down Round”), then the Conversion Price hereof shall be proportionately reduced to match the price per share of the Purchase Rights. For purposes of clarification, if the conversion price of the Note is $2.00, and if the Company sells Common Stock at $1.50 per share at any time after the date hereof, then the Conversion Price of this Note would be adjusted to $1.50. This Section shall not apply to an Exempt Issuance as defined in Section 7(c).

(c)       The issuance of a Purchase Right that is an Exempted Issuance (as defined below) shall not constitute a Down Round for purposes of this Agreement. “Exempt Issuance” means the issuance of (a) shares of Common Stock or options to employees, officers or directors of the Company or consultants to the Company pursuant to any stock or option plan duly adopted for such purpose, by a majority of the non-employee members of the Board of Directors or a majority of the members of a committee of non-employee directors established for such purpose for services rendered to the Company, provided, however, such issuance shall not exceed fifteen percent (15%) of the shares of Common Stock issued and outstanding as of the date hereof, (b) securities upon the exercise or exchange of or conversion of any securities exercisable or exchangeable for or convertible into shares of Common Stock issued and outstanding on the date of this Agreement, provided that such securities have not been amended since the date of this Agreement to increase the number of such securities or to decrease the exercise price, exchange price or conversion price of such securities (other than in connection with stock splits or combinations) or to extend the term of such securities, (c) securities issued pursuant to acquisitions or strategic transactions approved by a majority of the disinterested directors of the Company or securities issued in financing transactions, the primary purpose of which is to finance acquisitions or strategic transactions approved by a majority of the disinterested directors of the Company, provided that such securities are issued as “restricted securities” (as defined in Rule 144) and carry no registration rights that require or permit the filing of any registration statement in connection therewith, and provided that any such issuance shall only be to a Person (or to the equityholders of a person or entity) which is, itself or through its subsidiaries, an operating company or an owner of an asset in a business synergistic with the business of the Company and shall provide to the Company additional benefits in addition to the investment of funds, but shall not include a transaction in which the Company is issuing securities primarily for the purpose of raising capital or to an entity whose primary business is investing in securities, (d), shares of Common Stock, options or convertible securities issued to banks, equipment lessors or other financial institutions, or to real property lessors, pursuant to a debt financing, equipment leasing or real property leasing transaction approved by a majority of the disinterested directors of the Company, (e) shares of Common Stock, options or convertible securities issued to in connection with the provision of goods pursuant to transactions approved by a majority of the disinterested directors of the Company and (f) shares of Common Stock, options or convertible securities issued in connection with sponsored research, collaboration, technology license, development, marketing or other similar agreements or strategic partnerships approved a majority of the disinterested directors of the Company but shall not include a transaction in which the Company is primarily issuing Common Stock or Common Stock equivalents primarily for the purpose of raising capital or to a person or an entity whose primary business is investing in securities.

(a)       The non-payment, when due or upon demand, of any principal or interest pursuant to this Note;

(b)       The material breach of any representation or warranty in this Note. In the event the Holder becomes aware of a breach of this Section 8(b), the Holder shall notify the Company in writing of such breach and the Company shall have five business days after notice to cure such breach;

(c)       The breach of any covenant or undertaking, not otherwise provided for in this Section 8;

(d)       The commencement by the Company of any voluntary proceeding under any bankruptcy, reorganization, arrangement, insolvency, readjustment of debt, receivership, dissolution, or liquidation law or statute of any jurisdiction, whether now or hereafter in effect; or the adjudication of the Company as insolvent or bankrupt by a decree of a court of competent jurisdiction; or the petition or application by the Company for, acquiescence in, or consent by the Company to, the appointment of any receiver or trustee for the Company or for all or a substantial part of the property of the Company; or the assignment by the Company for the benefit of creditors; or the written admission of the Company of its inability to pay its debts as they mature;

(e)       The commencement against the Company of any proceeding relating to the Company under any bankruptcy, reorganization, arrangement, insolvency, adjustment of debt, receivership, dissolution or liquidation law or statute of any jurisdiction, whether now or hereafter in effect, provided, however, that the commencement of such a proceeding shall not constitute an Event of Default unless the Company consents to the same or admits in writing the material allegations of same, or said proceeding shall remain undismissed for 20 days; or the issuance of any order, judgment or decree for the appointment of a receiver or trustee for the Company or for all or a substantial part of the property of the Company, which order, judgment or decree remains undismissed for 20 days; or a warrant of attachment, execution, or similar process shall be issued against any substantial part of the property of the Company;

(f)        The Company liquidates, transfers, sells or assigns substantially all of its assets or elects to wind down its operations or dissolve;

(g)       The Company fails to maintain irrevocable TA instruction or file with the Company’s transfer agent or switches transfer agents without at least twenty (20) day’s prior written notice to Holder after the Company has engaged a transfer agent;

(h)       The Company fails to maintain DTC or DWAC eligibility;

(i)        The Company fails to stay current in its SEC reporting obligations, if applicable;

(j)        The Company fails to deliver the Holder and/or its assigns the shares of Common Stock rightfully listed in the Conversion Notice within three (3) business days.

(k)       The Company defaults on any other future debt exceeding a value of $50,000.

(l)        The Company breaches any other agreement it has with Holder or its assigns.

(m)     The Company interferes with Holder’s or its assigns’ efforts to remove the restrictive legend from the Common Stock issued as a result of conversion of the Note when Holder or its assign has provided an attorney opinion letter opining that the shares are eligible to have the legend removed pursuant to Rule 144 or otherwise.

There will be no cure period available for the Event of Default as defined in Section 8(d) and 8(e); Upon the occurrence of any Event of Default, and provided such Event of Default as defined in Section 8(a) through 8(c), and 8(f) through 8(m), has not been cured by the Company within five (5) business days after the occurrence of such Event of Default (except a payment default of any interest, principal and/or other amount when due, of which no cure period is available), the Holder, may, by written notice to the Company, declare all or any portion of the unpaid Principal Amount due to Holder, together with all accrued interest thereon, immediately due and payable (without advanced notice as may otherwise by required hereunder); provided that upon the occurrence of an Event of Default as set forth in paragraph (d) or paragraph (e) hereof, all or any portion of the unpaid Principal Amount due to Holder, together with all accrued interest thereon, shall immediately become due and payable without any such notice. Holder shall also have all other remedies available under law and equity. There shall be a late charge equal to 18% of the amount of any unpaid principal plus any interest accrued as of the due date.

In the event that Holder at its sole discretion elects to allow the Company to continue with repayment of the principal and interest on this Note after an Event of Default, the interest rate on the unpaid principal of this Note will change to 18% or the highest interest rate currently allowable under Nevada law for loans of this amount (the “Default Interest Rate”). In the event of any changes under Nevada law relating to the increases or decreases of allowable interest rates, this Note will be changed to the highest amount allowable under Nevada law without notification or further ratification. As of the date of Default or any Event of Default, assuming the Holder allows reinstatement or continuation of this Note, the Default Interest Rate shall become the new rate of interest on this Note.

Any payments that the Holder allows under this section shall be made through a wire transfer of funds or Certified Check.

Upon the occurrence of any Default or Event of Default, the Holder at any time, at its sole discretion, may elect to immediately (without prior notice) convert the outstanding principal amount of this Note, or any portion of the principal amount hereof, and any accrued interest, in whole or in part, into shares of the common stock of the Company, according to the terms of this Note.

If to the Company:

Cardiff Lexington Corporation and subsidiaries

3753 Howard Hughes Parkway, Suite 200,

Las Vegas, NV 89169

Attn: Alex H. Cunningham – Chief Executive Officer

If to the Holder:

Greentree Financial Group Inc.

900 S. Pine Island Road, Suite 310

Plantation, FL 33324

Attn: R. Chris Cottone – Vice President

(a)      Organization, Good Standing and Power. The Company is a corporation duly incorporated, validly existing and in good standing under the laws of the State of Nevada and has the requisite corporate power to own, lease and operate its properties and assets and to conduct its business as it is now being conducted.

(b)      Authorization; Enforcement. The Company has the requisite corporate power and authority to enter into and perform this Note and to issue and sell this Note. The execution, delivery and performance of this Note by the Company, and the consummation by it of the Transactions contemplated hereby, have been duly and validly authorized by all necessary corporate action. This Note, when executed and delivered, will constitute a valid and binding obligation of the Company enforceable against the Company in accordance with its terms, except as such enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium, liquidation, conservatorship, receivership or similar laws relating to, or affecting generally the enforcement of, creditor’s rights and remedies or by other equitable principles of general application.

(c)      Disclosure. Neither this Note nor any other document, certificate or instrument furnished to the Holder by or on behalf of the Company in connection with the transactions contemplated by this Note contains any untrue statement of a material fact or omits to state a material fact necessary in order to make the statements made herein or therein, in the light of the circumstances under which they were made herein or therein, not misleading.

(a)       Holder is acquiring the Note with the intent to hold as an investment and not with a view of distribution.

(b)       Holder is an “accredited investor” within the definition contained in Rule 501(a) under the Securities Act of 1933, as amended (the “Securities Act”), and is acquiring the Note for its own account, for investment, and not with a view to, or for sale in connection with, the distribution thereof or of any interest therein. Holder has adequate net worth and means of providing for its current needs and contingencies and is able to sustain a complete loss of the investment in the Note, and has no need for liquidity in such investment. Holder, itself or through its officers, employees or agents, has sufficient knowledge and experience in financial and business matters to be capable of evaluating the merits and risks of an investment such as an investment in the Securities, and Holder, either alone or through its officers, employees or agents, has evaluated the merits and risks of the investment in the Note.

(c)       Holder acknowledges and agrees that it is purchasing the Note hereunder based upon its own inspection, examination and determination with respect thereto as to all matters, and without reliance upon any express or implied representations or warranties of any nature, whether in writing, orally or otherwise, made by or on behalf of or imputed to the Company.

(d)       Holder has taken no action which would give rise to any claim by any person for brokerage commissions, transaction fees or similar payments relating to this Note or the transactions contemplated hereby. Holder acknowledges and agrees that neither the Company nor its employee(s), member(s), beneficial owner(s), or partner(s) solicited Holder to enter into this Note and consummate the transactions described in this Note.

EACH OF THE PARTIES HERETO HEREBY WAIVES TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY WITH RESPECT TO ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF, UNDER OR IN CONNECTION WITH THIS NOTE OR THE TRANSACTIONS CONTEMPLATED BY THIS NOTE. EACH OF THE PARTIES HERETO HEREBY (A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR ATTORNEY OF THE OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER AND (B) ACKNOWLEDGES THAT IT HAS BEEN INDUCED TO ENTER INTO THIS NOTE AND THE TRANSACTIONS CONTEMPLATED BY THIS NOTE, AS APPLICABLE, BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION 13.

[Signature page follows]

In witness whereof, the below parties signed and sealed this Note as of above date written.

Exhibit A

Schedule of Loan Advances (Additional Sheets may be Attached if Necessary)

EXHIBIT B -- NOTICE OF CONVERSION

The undersigned hereby elects to convert $ _________________ principal amount of the Note (defined below) into that number of shares of Common Stock to be issued pursuant to the conversion of the Note (“Common Stock”) as set forth below, of Cardiff Lexington Corporation, a Nevada corporation (the “Company”), according to the conditions of the Convertible Promissory Note of the Company dated as of December 29, 2025 (the “Note”), as of the date written below. No fee will be charged to the Holder for any conversion, except for transfer taxes, if any.

Box Checked as to applicable instructions:

By: ___________________________

Name:

Title:

Date: ___________________________