WASHINGTON – All D.C. taxis have to have credit-card readers by the end of August, but so far the cab companies have been slow to adopt the new technology.

Ron Linton, chairman of the D.C. Taxicab Commission, tells the Washington City Paper that only about 200 of the city’s cabs have installed the readers so far. Installation began June 1.

Linton tells the City Paper that the companies are still negotiating with providers, and that the number of reader-equipped cabs will rocket upward soon.

Each cab with a reader will charge an extra 50 cents to each trip and another $1 surcharge for groups of two to four passengers, whether the riders pay with cash or a card.

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