WASHINGTON (AP) — Metro is encouraging customers to switch from using paper farecards to plastic ones.

Starting on Monday, Metro is encouraging customers to switch by allowing travelers to transfer up to $20 from a paper farecard to a plastic SmarTrip card. Previously, the maximum transfer was $7. Metro says 90 percent of bus riders and more than 80 percent of train riders currently use SmarTrip cards.

Beginning July 1, customers that use paper farecards will be charged an additional $1 per trip. SmarTrip cards cost $5, but Metro says it plans to offer customers who purchase new cards a $3 rebate when they register the card online. SmarTrip cards were first introduced in 1996.

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