UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of May, 2023

Commission File Number 001-37928

ChipMOS TECHNOLOGIES INC.

(Translation of Registrant’s Name Into English)

No. 1, R&D Rd. 1, Hsinchu Science Park

Hsinchu, Taiwan

Republic of China

(Address of Principal Executive Offices)

(Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.)

Form 20-F ☒ Form 40-F ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

EXHIBIT INDEX

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ChipMOS REPORTS FIRST QUARTER 2023 RESULTS

Hsinchu, Taiwan – May 4, 2023 - ChipMOS TECHNOLOGIES INC. (“ChipMOS” or the “Company”) (Taiwan Stock Exchange: 8150 and NASDAQ: IMOS), an industry leading provider of outsourced semiconductor assembly and test services (“OSAT”), today reported consolidated financial results for the first quarter ended March 31, 2023. All U.S. dollar figures cited in this press release are based on the exchange rate of NT$30.48 against US$1.00 as of March 31, 2023.

All the figures were prepared in accordance with Taiwan-International Financial Reporting Standards (“Taiwan-IFRS”).

Revenue for the first quarter of 2023 was NT$4,605.1 million or US$151.1 million, a decrease of 1.7% from NT$4,686.2 million or US$153.7 million in the fourth quarter of 2022 and a decrease of 31.5% from NT$6,725.2 million or US$220.6 million for the same period in 2022. The decline reflects the industry-wide impact of macroeconomic weakness, certain end market demand softness and ongoing customer inventory adjustments.

Net non-operating income in the first quarter of 2023 was NT$43.5 million or US$1.4 million, compared to net non-operating expenses of NT$130.0 million or US$4.3 million in the fourth quarter of 2022. The increase of net non-operating income compared to the fourth quarter of 2022 is mainly due to a decrease of the foreign exchange losses of NT$173 million or US$5.7 million. Net non-operating income in the first quarter of 2022 was NT$229.0 million or US$7.5 million. The difference is mainly due to an increase of the foreign exchange losses of NT$187 million or US$6.1 million from the foreign exchange gains of NT$143 million or US$4.7 million in the first quarter of 2022 to the foreign exchange losses of NT$44 million or US$1.4 million in the first quarter of 2023.

Net profit attributable to equity holders of the Company for the first quarter of 2023 was NT$202.4 million or US$6.6 million, and NT$0.28 or US$0.01 per basic common share, as compared to NT$154.9 million or US$5.1 million, and NT$0.22 or US$0.01 per basic common share in the fourth quarter of 2022. This compares to NT$1,224.7 million or US$40.2 million, and NT$1.68 or US$0.06 per basic common share in the first quarter of 2022. Net earnings for the first quarter of 2023 were US$0.18 per basic ADS, compared to US$0.14 per basic ADS for the fourth quarter of 2022 and US$1.11 per basic ADS in the first quarter of 2022.

Free cash flow for the first quarter of 2023 was NT$1,033.0 million or US$33.9 million, with a balance of cash and cash equivalents was NT$11,735.8 million or US$385.0 million.

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First Quarter 2023 Investor Conference Call / Webcast Details

Date: Thursday, May 4, 2023

Time: 3:00PM Taiwan (3:00AM New York)

Dial-In: +886-2-33961191

Password: 9200504 #

Webcast and Replay: https://www.chipmos.com/chinese/ir/info2.aspx

Replay Starting 2 Hours After Live Call Ends

Language: Mandarin

Note: A transcript will be provided on the Company’s website in English following the conference call to help ensure transparency, and to facilitate a better understanding of the Company’s financial results and operating environment.

About ChipMOS TECHNOLOGIES INC.:

ChipMOS TECHNOLOGIES INC. (“ChipMOS” or the “Company”) (Taiwan Stock Exchange: 8150 and NASDAQ: IMOS) (www.chipmos.com) is an industry leading provider of outsourced semiconductor assembly and test services. With advanced facilities in Hsinchu Science Park, Hsinchu Industrial Park and Southern Taiwan Science Park in Taiwan, ChipMOS is known for its track record of excellence and history of innovation. The Company provides end-to-end assembly and test services to leading fabless semiconductor companies, integrated device manufacturers and independent semiconductor foundries serving virtually all end markets worldwide.

Forward-Looking Statements

This press release may contain certain forward-looking statements. These forward-looking statements may be identified by words such as ‘believes,’ ‘expects,’ ‘anticipates,’ ‘projects,’ ‘intends,’ ‘should,’ ‘seeks,’ ‘estimates,’ ‘future’ or similar expressions or by discussion of, among other things, strategies, goals, plans or intentions. These statements may include financial projections and estimates and their underlying assumptions, statements regarding plans, objectives and expectations with respect to future operations, products and services, and statements regarding future performance. Actual results may differ materially in the future from those reflected in forward-looking statements contained in this document, due to various factors. Further information regarding these risks, uncertainties and other factors are included in the Company’s most recent Annual Report on Form 20-F filed with the U.S. Securities and Exchange Commission (the “SEC”) and in the Company’s other filings with the SEC.

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