Where the purchase arrives matters
Pennsylvania began enforcing new local-sales-tax sourcing rules October 1. The Department of Revenue says vendors already required to collect state sales tax must also collect Philadelphia's two-percent local tax or Allegheny County's one-percent tax on taxable deliveries into those counties.
Before the change, local tax generally followed the seller's location. It now follows the destination of the taxable product or service. That can change checkout treatment when the seller is outside the county but the purchase arrives inside it.
A collection change is not a new state rate
The state six-percent sales tax itself has not changed. The department also says use-tax rules remain the same: if required sales tax is not collected, use tax may still be owed where the taxable item or service is used. A missing checkout line is not proof that the obligation vanished.
Act 21 became law July 12 with a retroactive tax-year effective date, but the department delayed enforcement until October 1 to allow vendors to adjust. Check the delivery location and actual taxable purchase before disputing a local-tax line. The fresh enforcement change is about sourcing, not a statewide tax increase on every transaction or a refund guarantee for prior orders.