According to the Constitution of pakistan levying of sales tax on services:

The responsibility of the Federation

The responsibility of FBR

The responsibility of provinces

Joint responsibility of the Federation and the provinces

Sales Tax Act, 1990 replaced the 1951 Act and introduced VAT model for taxation of goods.

Being a matter not included in the Federal Legislative List or the Concurrent Legislative List in the Constitution,

sales tax on services remained in the Provincial domain.