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 November, 2021

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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Exhibit 99.1

ChipMOS REPORTS THIRD QUARTER 2021 RESULTS

Hsinchu, Taiwan – November 8, 2021 - 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 third quarter ended September 30, 2021. All U.S. dollar figures cited in this press release are based on the exchange rate of NT$27.84 against US$1.00 as of September 30, 2021.

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

Revenue for the third quarter of 2021 was NT$7,161.0 million or US$257.2 million, an increase of 2.6% from NT$6,982.3 million or US$250.8 million in the second quarter of 2021 and an increase of 25.9% from NT$5,686.1 million or US$204.2 million for the same period in 2020.

Net non-operating income in third quarter of 2021 was NT$147.5 million or US$5.3 million, compared to net non-operating expenses NT$18.9 million or US$0.7 million in the second quarter of 2021. The difference is primarily due to an increase in the share of gain of associates accounted for using equity method of NT$85 million or US$3.1 million, a lower foreign exchange loss of NT$62 million or US$2.2 million and an increase of gain on valuation of financial assets at fair value through profit or loss of NT$15 million or US$0.5 million. Net non-operating expenses in third quarter of 2020 were NT$178.5 million or US$6.4 million.

Net profit attributable to equity holders of the Company for the third quarter of 2021 was NT$1,398.9 million or US$50.2 million, and NT$1.93 or US$0.07 per basic common share, as compared to NT$1,283.6 million or US$46.1 million, and NT$1.76 or US$0.06 per basic common share in the second quarter of 2021. This compares to NT$423.4 million or US$15.2 million, and NT$0.58 or US$0.02 per basic common share in the third quarter of 2020. Net earnings for the third quarter of 2021 were US$1.38 per basic ADS, compared to US$1.27 per basic ADS for the second quarter of 2021 and US$0.42 per basic ADS in the third quarter of 2020.

Free cash flow for the first nine months of 2021 was NT$1,416.4 million or US$50.9 million, with a balance of cash and cash equivalents was NT$5,188.8 million or US$186.4 million.

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Third Quarter 2021 Investor Conference Call / Webcast Details

Date: Monday, November 8, 2021

Time: 4:00PM Taiwan (3:00AM New York)

Dial-In: +886-2-21928016

Password: 655980 #

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

Replay Starting 2 Hours After Live Call Ends

Language: Mandarin

About ChipMOS TECHNOLOGIES INC.:

ChipMOS TECHNOLOGIES INC. (“ChipMOS” or the “Company”) (Taiwan Stock Exchange: 8150 and NASDAQ: IMOS) (https://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 provide assembly and test services to a broad range of customers, including leading fabless semiconductor companies, integrated device manufacturers and independent semiconductor foundries.

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, strategy, 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, including the ongoing impact of COVID-19. 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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