Company: GCTS
Filing Date: 2025-04-23
Form Type: S-3
Source: 0001104659-25-038103
Chunk: 1

Company: GCT Semiconductor Holding, Inc.
Filing Date: 2025-04-23
Form: S-3
Chunk 1
---
 statement number of the earlier effective registration statement for the same offering. ¨

If this form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ¨

If this form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.¨

Indicate by check mark whether the registrant is a large accelerated
filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions
of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging
growth company” in Rule 12b-2 of the Exchange Act.

| Large accelerated filer | ¨ |     | Accelerated filer         | ¨ |
| Non-accelerated filer   | x |     | Smaller reporting company | x |
|                         |   |     | Emerging growth company   | x |

If an emerging growth company,
indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial
accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ¨

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

<div align='center'>EXPLANATORY NOTE</div>

As of April 1, 2025,
we became eligible under Securities and Exchange Commission (“SEC”) rules to use a short-form registration statement
on Form S-3. This registration statement on Form S-3 is being filed in part to update and replace our registration statement
on Form S-1 (Registration No. 333-279600), which was declared effective by the SEC on June 6, 2024 (the “S-1 Registration
Statement