When invoicing for small brands, it is usually said that the manual version of the invoice code is a 12-digit code. The first position of the ordinary invoice is the tax bureau code 1 national tax, 2 local tax, the 2nd to 5th position is the administrative division code of the first 4 position, the last two digits of the code in the 6th to 7th position of the year, such as 2005, are 05, the 8th position is the invoice industry code, the 9th position is the invoice category code, the 10th position is the amount version code, and the 11th to 12th digits are the batch number, printed in the order of the batch number of the year.