On February 24, 2021 and May 5, 2020, we received loans (“PPP Loans”) from US Bank in the amounts of $1.2 million (“Loan 1”) and $1.2 million (“Loan 2”), respectively, to fund payroll, rent and utilities through the Paycheck Protection Program (“PPP”). We repaid $19 thousand during the three months ended March 31, 2025 for Loan 1, which was due and repaid in full on May 5, 2025. As of December 31, 2025, the total principal outstanding under Loan 2 was $9 thousand, which was fully repaid on February 27, 2026. Interest expense for Loan 1 and Loan 2 for the three months ended March 31, 2026 and 2025 was immaterial.

On January 9, 2025, we and Yorkville entered into the Third Omnibus Amendment to the Yorkville Note, (the “Third Amendment”), pursuant to which, we and Yorkville agreed that for $1.5 million of the then current outstanding balance due under the Yorkville Note (principal and unpaid accrued interest), the fixed price for conversion will be modified to $1.752 per share, and for the remainder of the balance, the fixed price will not be changed but will remain $13.84185 per share as provided for in the Yorkville Note when we issued it on March 4, 2024. Further, the Third Amendment removed our obligation to make monthly payments to Yorkville, previously owing due to the occurrence of the Trigger Event, through the maturity date of the Yorkville Note of March 31, 2026. In exchange for this relief, the aggregate purchase price owed to us from the first Advance that occurs pursuant to the terms of the SEPA (the “Advance Proceeds”) will be paid by

Yorkville offsetting the amount of the Advance Proceeds against an equal amount outstanding under the Yorkville Note (first towards accrued and unpaid interest, and then towards outstanding principal and the corresponding payment premium in respect of such principal amount, if applicable), and that for any subsequent Advances pursuant to the terms of the SEPA, Yorkville will pay half of such Advance Proceeds directly to us and the other half of such Advance Proceeds will be paid by Yorkville offsetting the amount of the Advance Proceeds against an equal amount outstanding under the Yorkville Note (first towards accrued and unpaid interest, and then towards outstanding principal and the corresponding payment premium in respect of such principal amount, if applicable). On January 9, 2025, we delivered our first Advance Notice as defined under the SEPA for the sale of 295,000 shares of common stock. This resulted in the reduction of an additional $0.2 million in principal of the Yorkville Note.

On February 26, 2025, we and Yorkville entered into a Termination Agreement, pursuant to which the parties acknowledged the termination of the SEPA effective February 26, 2025. On February 26, 2025, we used a portion of the proceeds of the Lynrock Lake Term Loan to pay Yorkville an amount equal to $3.0 million in cash and issued to Yorkville the Yorkville Warrant to purchase 5,000,071 shares of our common stock at an exercise price of $1.20 per share to fully settle and discharge our obligations under the Yorkville Note and extinguish the Yorkville Note as having been fully performed. As a result of the extinguishment of the Yorkville Note, we recorded an expense of $1.9 million in other expense, net within the unaudited condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2025. The Yorkville Warrant was exercisable until February 26, 2030. The fair value of the Yorkville Warrant at issuance amounted to $3.0 million. On June 11, 2025, the Yorkville Warrant was amended to update the provisions that would trigger cash settlement such that, when such events occur, the holders of the warrants receive the same form of consideration as the underlying stockholders. Consequently, upon modification, the warrants were revalued and then reclassified to additional paid-in capital on the consolidated balance sheets. We determined the fair value of the Yorkville Warrant using the Black-Scholes Model through the modification. Refer to Note 3 - Fair Value Measurements for more information.

On January 9, 2025, we and Funicular Funds, LP (“Cable Car”) entered into an Omnibus Amendment (the “Cable Car Amendment”) to amend certain terms of the secured note purchase agreement by and between QT Imaging and Cable Car (the “Cable Car Note”), including a reduction of the conversion price for the Cable Car Note to $1.752 per share. Further, the Cable Car Amendment extended the maturity date for the Cable Car Note to March 31, 2026, in exchange for an extension fee (the “Extension Fee”) of $0.1 million to Cable Car, with such fee being added to the amount due and payable on such maturity date, unless the Cable Car Note is earlier converted pursuant to its terms, in which event the Extension Fee will also be converted. No interest will accrue or be due on the Extension Fee. Pursuant to the Cable Car Amendment, interest will accrue on the outstanding principal balance of the Cable Car Note at an annual rate equal to 6%, with interest being calculated based on a 365-day year and the actual number of days elapsed, to the extent permitted by applicable law. Interest will be due and payable on the maturity date for the Cable Car Note, unless the Cable Car Note is earlier converted pursuant to its terms, in which event such accrued and unpaid interest will also be converted. We recorded the Extension Fee of $0.1 million in other expense, net within the unaudited condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2025.

On February 26, 2025, we used a portion of the proceeds of the Lynrock Lake Term Loan to pay Cable Car an amount equal to the full principal, interest and fees amount of approximately $1.6 million in cash to fully settle and discharge our obligations under the Cable Car Note and extinguish the Cable Car Note as having been fully performed. As a result of the extinguishment of the Cable Car Note, we recorded an expense of $0.1 million in other expense, net within the unaudited condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2025.

On February 26, 2025, we entered into the Lynrock Lake Credit Agreement that provides the Lynrock Lake Term Loan with Lynrock Lake. The Lynrock Lake Credit Agreement is secured by a first priority lien on substantially all of our assets and provides for a term loan in the aggregate principal amount of $10.1 million at an interest rate of 10.0% per annum, compounded quarterly. Prior to the Second Amended Credit Agreement, the maturity date of the Lynrock Lake Credit Agreement was March 31, 2027 and is now March 31, 2029. The Lynrock Lake Term Loan will be repaid on the maturity date in an amount equal to the aggregate principal amount outstanding, together with all accrued and unpaid interest and any outstanding and payable fees.

Subject to the payment of the Make-Whole Amount (as defined in the Lynrock Lake Credit Agreement), we may at any time prior to the maturity date optionally prepay the term loan, in full or in part, upon irrevocable written notice of three business days prior to the proposed prepayment; provided that if such prepayment is to be funded with the proceeds of a refinancing or disposition, such notice of prepayment may be revoked if the financing or disposition is not consummated; provided further, that any such prepayment made in connection with, or in anticipation of, a Change of Control (as defined in the Lynrock Lake Credit Agreement) will also be subject to a prepayment premium equal to 20% of the amount of principal being prepaid (the “Prepayment Premium”).

• If on any date we or any of our subsidiaries will receive any cash proceeds from any Extraordinary Receipt (as defined in the Lynrock Lake Credit Agreement) in an amount equal to or exceeding $0.3 million in the aggregate, we will prepay the term loan within five business days of receipt of such cash proceeds, in an amount equal to 100% of the cash proceeds of such Extraordinary Receipt (as defined in the Lynrock Lake Credit Agreement);

• If any indebtedness will be incurred by us or any subsidiary thereof (excluding any indebtedness that the Lynrock Lake Credit Agreement permits us to incur), an amount equal to 100% of the net cash proceeds thereof will be applied on the date of incurrence or receipt toward the prepayment of the term loan;

• If on any date we or any of our subsidiaries will receive net cash proceeds in an amount equal to or exceeding (i) $0.3 million in any single transaction or series of related transactions or (ii) $0.3 million in the aggregate for all transactions during the term of the Lynrock Lake Credit Agreement from any Asset Sale (as defined in the Lynrock Lake Credit Agreement) or Recovery Event (as defined in the Lynrock Lake Credit Agreement) then we or such subsidiary will prepay the term loan, on or prior to the date which is five business days after the date of the realization or receipt by us or subsidiary in an amount equal to 100% of such proceeds; and

• Subject to the payment of the Prepayment Premium in addition to the Make-Whole Amount (as defined in the Lynrock Lake Credit Agreement), in the event that a Change of Control (as defined in the Lynrock Lake Credit Agreement) will occur, we will prepay all of the outstanding term loan, on or prior to the date which is two business days after the date of such Change of Control (as defined in the Lynrock Lake Credit Agreement).

There are no requirements to make any prepayment in the event that we sell any of our capital stock. In addition, at the option of Lynrock Lake, we will also make mandatory repayments of the term loan on a monthly basis, no later than five business days after the end of each month (provided that such date for payment is prior to the maturity date), if we or our subsidiaries receive payment of accounts receivable on or after January 1, 2026, in an amount equal to 15% of the aggregate amount of payments of accounts receivable actually received during such prior month, net of any cost of collection incurred not in the ordinary course of business. No Make-Whole Amount (as defined in the Lynrock Lake Credit Agreement) or Prepayment Premium is due or payable on any such mandatory prepayment as a result of receipt of accounts receivable on or after January 1, 2026. As of March 31, 2026, Lynrock Lake has not elected the repayment option in the amount equal to 15% of the aggregate amount of payments of accounts receivable actually received on or after January 1, 2026.

In connection with the Lynrock Lake Term Loan, we issued to Lynrock Lake the Lynrock Lake Warrant to purchase 20,333,623 shares of common stock at an exercise price of $1.20 per share. Upon the closing of the October 2025 Private Placement (as defined below), the number of shares which may be purchased upon exercise of the Lynrock Lake Warrant and the per share exercise price were adjusted to 24,396,416 and $1.0002, respectively. The Lynrock Lake Warrant is

exercisable until February 26, 2035. Lynrock Lake may cashless exercise the Lynrock Lake Warrant. The Lynrock Lake Warrant is also subject to anti-dilution adjustments to the exercise price and the number of shares which may be purchased upon exercise of the Lynrock Lake Warrant in the event that we issue shares of common stock (or derivative securities) at a price that is either less than the $1.0002 exercise price or the fair market value of a share of common stock from the immediately prior trading day. The fair value of the Lynrock Lake Warrant at issuance amounted to $16.5 million. On June 11, 2025, the Lynrock Lake Warrant was amended to update the provisions that would trigger cash settlement such that, when such events occur, the holders of the warrants receive the same form of consideration as the underlying stockholders. As equity classification is permitted for an instrument that requires net-cash settlement if the holders of the contract’s underlying shares receive the same form of consideration in transactions outside our control, consequently the warrants were revalued and then reclassified to additional paid-in capital on the consolidated balance sheet upon modification. We determined the fair value of the Lynrock Lake Warrant using the Black-Scholes pricing model through the modification. Refer to Note 3 - Fair Value Measurements for more information.

On August 26, 2025, we and Lynrock Lake entered into the First Amendment to the Lynrock Lake Credit Agreement (the “Lynrock Lake Amended Credit Agreement”) to add an additional tranche of $5.0 million (“Tranche B”) to the loan and increase the aggregate principal amount of the Lynrock Lake Term Loan to $15.1 million. The proceeds of Tranche B were used to repurchase the Yorkville Warrant. Tranche B was subject to the Tranche B Premium equal to 6% multiplied by the sum of (i) the principal of Tranche B being repaid plus (ii) all related accrued and unpaid interest. Subject to the payment of the Make-Whole Amount, if we received Net Cash Proceeds (as defined in the Lynrock Lake Credit Agreement) from any sale or issuance of our common stock, then we will, at the option of Lynrock Lake, prepay, or cause to be prepaid, Tranche B on or prior to the date which is thirty days after the date of the receipt by us of such Net Cash Proceeds in an amount equal to the lesser of (i) 100% of such Net Cash Proceeds or (ii) the principal amount of Tranche B on such date of prepayment, together with all accrued and unpaid interest thereon and any outstanding fees or premium, if any, payable in accordance with the Lynrock Lake Term Loan. Additionally, in connection with any mandatory prepayment of Tranche B on or prior to December 31, 2025, such mandatory prepayment will be subject to the payment of the Tranche B Premium instead of the Make-Whole Amount.

As of March 31, 2026, the outstanding amount of the Lynrock Lake Term Loan was $1.4 million, net of the unamortized debt discount of $8.7 million, and accrued interest was $1.2 million. Interest expense, including amortization of debt issuance costs, for the three months ended March 31, 2026 and 2025 was $1.0 million and $0.1 million, respectively.

In February 2026, we obtained waivers from Lynrock Lake in connection with debt covenant non-compliance related to the first three quarters of 2025. We were in compliance with the debt covenant covered by the Lynrock Lake Term Loan for the fourth quarter of 2025 and first quarter of 2026. The Lynrock Lake Term Loan has been classified as a noncurrent liability on the unaudited condensed consolidated balance sheets as of March 31, 2026 and December 31, 2025.