Income Tax Act Article 14-8

For the amount of tax in accordance with the provision of Article 14-5 paid by an individual on the income realized from the sales of house and land of a self-use residence, if he(or she) repurchases another house and land as his(or her) self-use residence within two years from the date on which the ownership transfer registration of house and land is completed or the transaction day of the right to use a house by creation of superficies, he (or she) may apply to be refunded from the tax payable at the ratio of the repurchase price in the original sales price.For an individual who purchases house and land for his self-use residence within two years from the date on which the ownership transfer registration of house and land is completed or the transaction day of the right to use a house by creation of superficies, when he (or she) sells another self-use resident house and land and declares his (or her) tax in accordance with the provision of Article14-5, he (or she) may deduct the amount of tax at the ratio provided in the preceding Paragraph with the limitation that it does not exceed the tax payable.If the house and land repurchased as self-use residence, as provided in the preceding two Paragraphs, was transferred or used for purposes other than the original purpose within five years from the day the transfer registration was completed for the reacquisition , the amount of deducted or refunded tax shall be paid back.
中文原文 所得稅法第14-8條
個人出售自住房屋、土地依第十四條之五規定繳納之稅額,自完成移轉登記之日或房屋使用權交易之日起算二年內,重購自住房屋、土地者,得於重購自住房屋、土地完成移轉登記或房屋使用權交易之次日起算五年內,申請按重購價額占出售價額之比率,自前開繳納稅額計算退還。
個人於先購買自住房屋、土地後,自完成移轉登記之日或房屋使用權交易之日起算二年內,出售其他自住房屋、土地者,於依第十四條之五規定申報時,得按前項規定之比率計算扣抵稅額,在不超過應納稅額之限額內減除之。
前二項重購之自住房屋、土地,於重購後五年內改作其他用途或再行移轉時,應追繳原扣抵或退還稅額。

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