Permanent Account Number (PAN) is a code that acts as identification of Indians, especially those who pay Income Tax. IT PAN card is issued under Section 139A of the Income Tax Act. 2  The PAN structure is as follows: AAAPL1234C: First five characters are letters, next four numerals, last character letter. 3  The first three letters are sequence of alphabets from AAA to ZZZ. 4  The fourth character informs about the type of holder of the card.