Enforcement Rules of Value-added and Non-value-added Business Tax Act Article 42

Where as business entity which computes its business tax based on the provisions of Section I of Chapter IV of the Act and has overpaid business tax as a result of applying zero tax rate under Article 7 of the Act, the amount of the tax refundable shall be the amount calculated by imposing on the zero-tax rate sales amount the tax rate prescribed in Article 10 of the Act.
中文原文 加值型及非加值型營業稅法施行細則第42條
本法第四章第一節規定計算稅額之營業人,適用本法第七條零稅率規定而有溢付營業稅額者,其可退還之稅額,為其零稅率銷售額依本法第十條所定徵收率計算之金額。

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