The Specifically Selected Goods and Services Tax Act Article 18
When a taxpayer fails to declare tax by the applicable deadline specified in Paragraph 1 or Paragraphs 3 to 5 of Article 16, or when, without due cause, the declared selling price is lower than the prevailing market price, the competent tax authority may assess a selling price and a tax amount, based on the prevailing market price or data obtained through investigation, and collect the tax.If any of the following circumstances occurs when a business entity sells the specifically selected goods or specifically selected services of Subparagraph 1 of Paragraph 1 of Article 2, the competent tax authority may assess a selling price and a tax amount, based on data obtained through investigation, and collect the tax:1. Accounting books have not been established, or an entry has not been made in the accounting books within the prescribed deadline, and following notification to make the entry, has still not been made, or accounting vouchers have been lost, or an audit by the competent tax authority is refused, or false entries have been made in the accounting books.2. When business operations have commenced without due registration pursuant to the Value-Added and Non-Value-Added Business Tax Act, or business operations have continued after application for cessation of business, and a selling price is not reported in accordance with regulations.When a manufacturer fails to declare tax within the deadline prescribed by Paragraph 2, Article 16, the competent tax authority shall issue a notification to the manufacturer requesting it to make payment and declare the tax within three days. If the manufacturer fails to do so within that deadline, the competent tax authority may assess a selling price and a tax amount, based on data obtained through investigation, and collect the tax.When, without due cause, the declared selling price of the manufacturer under the preceding paragraph is lower than the prevailing market price, the competent tax authority may assess a selling price and a tax amount, based on the market price or data obtained through investigation, and collect the tax.
中文原文 特種貨物及勞務稅條例第18條
納稅義務人屆第十六條第一項、第三項至第五項規定申報期限未申報或申報之銷售價格較時價偏低而無正當理由者，主管稽徵機關得依時價或查得資料，核定其銷售價格及應納稅額並補徵之。
營業人銷售第二條第一項第一款規定之特種貨物或特種勞務，有下列情形之一者，主管稽徵機關得依查得資料，核定其銷售價格及應納稅額並補徵之：
一、未設立帳簿、帳簿屆規定期限未記載且經通知補記載仍未記載、遺失帳簿憑證、拒絕稽徵機關調閱帳簿憑證或於帳簿為虛偽不實之記載。
二、未依加值型及非加值型營業稅法規定辦妥營業登記，即行開始營業，或已申請歇業仍繼續營業，而未依規定申報銷售價格。
產製廠商屆第十六條第二項規定申報期限未申報者，主管稽徵機關應通知於三日內繳稅補辦申報；屆期仍未辦理者，主管稽徵機關得依查得資料，核定其銷售價格及應納稅額並補徵之。
前項產製廠商申報之銷售價格較時價偏低而無正當理由者，主管稽徵機關得依時價或查得資料，核定其銷售價格及應納稅額並補徵之。
營業人銷售第二條第一項第一款規定之特種貨物或特種勞務，有下列情形之一者，主管稽徵機關得依查得資料，核定其銷售價格及應納稅額並補徵之：
一、未設立帳簿、帳簿屆規定期限未記載且經通知補記載仍未記載、遺失帳簿憑證、拒絕稽徵機關調閱帳簿憑證或於帳簿為虛偽不實之記載。
二、未依加值型及非加值型營業稅法規定辦妥營業登記，即行開始營業，或已申請歇業仍繼續營業，而未依規定申報銷售價格。
產製廠商屆第十六條第二項規定申報期限未申報者，主管稽徵機關應通知於三日內繳稅補辦申報；屆期仍未辦理者，主管稽徵機關得依查得資料，核定其銷售價格及應納稅額並補徵之。
前項產製廠商申報之銷售價格較時價偏低而無正當理由者，主管稽徵機關得依時價或查得資料，核定其銷售價格及應納稅額並補徵之。