The National Fiscal Service explains

Customs clearance is to be made within four business hours from the moment of presenting the goods and commercial vehicles subject to processing to the customs officers (if goods and commercial vehicles are subject to customs clearance according to the Customs Code of Ukraine), and submitting a customs declaration or the document that can replace it as set out in the legislation as well as all necessary documents and information, the message of the National Fiscal Service of Ukraine says.  

In so doing, the said above period can be prolonged for required formalities solely in case of:

1) making customs formalities outside the revenue authority location  (pursuant to part 8 of article 247 of the Customs Code of Ukraine – hereinafter the CCU);

2) the intent expressed by a declarant or an authorized person, which is confirmed in writing, to file additional documents or information on an international business transaction or  product features;

3) making research (analysis, expertise) of product patterns and samples, if the products are not released (according to part 21 of article 356 of the CCU);

4) revealing violations of the customs rules, if the goods are not released (according to part 5 of article 255 of the CCU);

5) deterring the customs clearance procedure pursuant to the Law of Ukraine dd. 02.12.2010 No. 2735 – VI On Public Market Oversight and Control of Non-Food Products;

6) submitting additional documents (according to part 3 of article 53 of the CCU).

The procedure for customs clearance of goods and commercial vehicles is governed by chapter VIII of the Customs Code of Ukraine.