Company: QTIWW
Filing Date: 2025-03-03
Form Type: 424B3
Source: 0001844505-25-000031
Chunk: 1

Company: QT IMAGING HOLDINGS, INC.
Filing Date: 2025-03-03
Form: 424B3
Chunk 1
---
 Prospectus or this Supplement No. 14 or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

<div align='center'>The date of this prospectus supplement is March 3, 2025.</div>

### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549
#### _________________________________________

#### FORM 8-K
#### _________________________________________

### CURRENT REPORT

#### Pursuant to Section 13 or 15(d)

#### of the Securities Exchange Act of 1934

#### February 26, 2025

#### Date of Report (Date of earliest event reported)
<div align='center'>________________________________________________________</div>

#### QT Imaging Holdings, Inc.
<div align='center'>(Exact name of Registrant as Specified in Charter)

________________________________________________________</div>

| Delaware                                                     |     | 001-40839    |     | 86-1728920             |
| (State or Other Jurisdiction of                              |     | (Commission  |     | (IRS Employer          |
| Incorporation or Organization)                               |     | File Number) |     | Identification Number) |
| 3 Hamilton Landing, Suite 160                                |     |              |     |                        |
| Novato, CA 94949                                             |     |              |     |                        |
| (Address of principal executive offices, including Zip Code) |     |              |     |                        |
| (650) 276-7040                                               |     |              |     |                        |
| (Registrant's telephone number, including area code)         |     |              |     |                        |

<div align='center'>________________________________________________________</div>

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions ( see General Instruction A.2. below):

| o |     | Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)                  |
| o |     | Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)                 |
| o |     | Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) |
| o |     | Pre-commencement communications pursuant to Rule 13e-4(c) under