Starting Monday, the TTC will allow its customers to board streetcars through any door.

All-door boarding was introduced on 504 King streetcars at the beginning of this year and now it is being implemented on all streetcar lines across the transit system.

While on board the streetcar, customers will have to have proof of payment, which includes a transfer, Metropass, as well as a day and weekly pass, or a PRESTO card.

On older streetcars, those paying with tickets, tokens or cash will still have to board through the front doors to receive a transfer.

Those hopping aboard a new streetcar can get on at any door and pay at the Fare and Transfer machine to get their proof-of-purchase.

Those who do not have a proof of purchase could face a fine and even stiffer penalties may be applied for repeat offenders, the TTC says.

Mayor John Tory told reporters last December that all-door boarding would shave five to six minutes off of the King streetcar route.