Virginia has become the latest state to link its electronic toll collection system to E-ZPass, allowing drivers with the appropriate transponder to use express toll lanes on many highways along the East Coast.

The new setup allows Virginia's 495,000 Smart Tag users to travel quickly through electronic tolls between Virginia and Massachusetts, and in West Virginia and soon New Hampshire, Maine and Illinois. Likewise, drivers who have E-ZPass can now use it on the Dulles Toll Road, Dulles Greenway and Virginia's five other toll facilities.

"This is such a common-sense thing to do," Virginia Transportation Commissioner Philip A. Shucet said yesterday during a startup ceremony near the main toll booth on the Greenway. "With these two systems joining each other, we can do our part in helping to make people's time a little more available."

New purple signs advertising both Smart Tag and E-ZPass lined Northern Virginia's toll roads yesterday, and drivers had no trouble zipping through with either system.

Washington area drivers, some of whom live in an E-ZPass state and work in a Smart Tag one, or vice versa, rejoiced at the merger. Some can now ditch one of their two transponders, while others can stop hunting for toll change.

"I've been looking forward to this for a long time," said Shawn Flaherty, a Loudoun County resident who uses her Smart Tag on the Greenway and Toll Road each day and has fumed every time she has traveled to New York and been slowed by lengthy waits to pay cash tolls. "The lines get pretty long, and you look at those E-ZPass lines go pretty quickly and you think, 'Whoa, if my pass just worked.' "

There is one downside for Smart Tag users. Transportation officials said it is probable that a $1 monthly fee will be instituted in the next few months to cover the costs of joining the E-ZPass network, which counts 11 million users. State officials said it cost nearly $2.5 million to link to the system, plus a one-time fee of $250,000 to join the network and an annual fee of $70,000. Officials also said charging a fee would bring the system in line with other E-ZPass states, some of which charge as little as $3 a year and others $1 or $2 a month.

Aside from easing commutes and long road trips, improving technology is critical to the state's plans to build express toll roads in Northern Virginia. Virtually every new major road Virginia officials are considering, as well as many proposed in Maryland, would include tolls. All of the proposals rest on claims that fares can be collected without slowing traffic.

Lamenting the plight of drivers behind him who were still fumbling for change to get onto the Greenway, Shucet said, "Part of our assessment ought to be whether we want to provide drivers with tags" so that everyone can move quickly through the toll plazas.

Concerns about traffic tie-ups at cash toll booths led to the phasing-out of many toll stations. Exact change lanes have helped in places where they have remained, and some facilities allow tokens as an added convenience, but transportation experts say that nothing has eased delays like the electronic systems.

They, too, have made major strides in recent years. At first, drivers were happy enough not to have to stop, proceeding through special lanes at 5 to 10 mph. But now some facilities, including the Dulles Toll Road and New Jersey Turnpike, are capable of charging tolls as cars pass through at the speed limit.

For users, the Smart Tag and E-ZPass systems work in about the same way: Motorists maintain an account that can be linked to a credit card from which tolls are deducted.

Fairfax lawyer Dan Gray said he's delighted to have the systems linked. He and his wife decided to sign up for E-ZPass a few months ago after weighing whether they preferred to save time on their trips to the Jersey Shore or at toll plazas in Northern Virginia. Now that he can do both, Gray said he's pleased by the convenience. "I don't have to worry about going to the bank so I'll have change," he said. "I'm thrilled."

Raphael White accepts a toll at the Dulles Toll Road plaza, where signs indicate that Virginia's Smart Tag is now part of the E-ZPass system. The E-ZPass works on all Virginia toll roads. The Smart Tag transponder now can pay tolls between Virginia and Massachusetts.Transportation Commissioner Philip A. Shucet said making Smart Tag part of the E-ZPass system was common sense.