If you’re planning to buy something from Amazon.com, you might want to get it today because tomorrow the online retailer will begin billing you for Pennsylvania’s 6 percent sales tax.

Sept. 1 is the deadline for e-commerce retailers like Amazon that have a presence in the state (Amazon has a new distribution center) to begin collecting sales tax.

It is a move that has been years in the making, as the state has sought ways to both raise revenue and even the playing field for businesses.

Businesses that do not become registered and begin collecting Pennsylvania sales tax by Sept. 1 will face a variety of escalating enforcement options over time, including assessment, audit, lien or referral to a collection agency or the Office of Attorney General.