Income Basic Tax Act Article 13

The amount of basic tax of an individual shall be the amount of basic income as calculated in accordance with Article 12 and Paragraph 1 of the preceding article with a deduction of NT$6,000,000 and then multiplied by the tax rate of twenty percent. However, in the case where income tax has been paid on the income under Subparagraph 1 of Paragraph 1 of Article 12, in accordance with the tax laws of the source jurisdiction of that income, such tax paid may be credited against the basic tax. The credited amount shall not exceed the amount of basic tax which, computed by the above mentioned method, is increased due to including such income.When a taxpayer applies for tax credit as described in the preceding paragraph, he or she shall present the evidence of tax payment certificates issued by the tax authorities of the said source jurisdiction for the same tax year and attested to by an overseas agency of the Republic of China or other organizations recognized by the Government of the Republic of China in the said locality.Paragraph 2, Article 3 shall apply mutatis mutandis to the calculation for adjustment and public announcement of the amount of the deduction prescribed in Paragraph 1.
中文原文 所得基本稅額條例第13條
個人之基本稅額,為依第十二條及前條第一項規定計算之基本所得額扣除新臺幣六百萬元後,按百分之二十計算之金額。
但有第十二條第一項第一款規定之所得者,其已依所得來源地稅法規定繳納之所得稅,得扣抵之。
扣抵之數不得超過因加計該項所得,而依前段規定計算增加之基本稅額。
前項扣抵,應提出所得來源地稅務機關發給之同一年度納稅憑證,並取得所在地中華民國駐外機構或其他經中華民國政府認許機構之驗證。
第一項規定之扣除金額,其計算調整及公告方式,準用第三條第二項之規定。

English translation for reference only; the Chinese text prevails. Not legal advice.