When the Massachusetts Department of Transportation replaced its toll booths with electronic EZ Pass gantries last fall, they may have made driving easier. But they also took down most of the signs saying where and how much the tolls are.

Alexis Tsapatsaris of Dracut takes the Mass Pike frequently between the Back Bay and I-95. The trip previously went through two tolls.

“The only way I knew there was a toll there was that there used to be a toll booth there,” she said. “Then I received the bill. That’s when I learned that between Boston and I-95 there were now three times they charge you.”

A new toll was created for through traffic at Newtonville. But there were no signs announcing the change.

“There were no fees posted, nothing to indicate that they had changed the fees,” Tsapatsaris said.

For visitors from out of state, it may come as a bigger surprise. Peter Keck of Wisconsin was worrying about tolls when bringing a car back to the Logan Airport rental car return.

“I was here in May, and I knew that they had tolls that you couldn’t pay with cash. So I asked when I got my car… yesterday morning and they said that I would have the EZ Pass in my rental car, but when I got in my car it was so new, they hadn’t put it in yet,” Keck said. “So I am a little worried that I went through two tolls and didn’t pay for them.”

Specifically, Keck said he took the Williams Tunnel in both directions, which would incur two tolls.

Locals also may be surprised by tolls in the tunnels and on the Tobin Bridge. Where previously there were only tolls coming into the city, they’re now in both directions — ostensibly, at half the price.

So what are drivers to do? Tsapatsaris wrote to Attorney General Maura Healey’s office on behalf of all tollpayers.

“Dear AG’s office,” she wrote. “These new fees are not posted. Instead, a threat is posted about big fines for not having EZ Pass. Please take us into consideration and advocate to lower these fees and clearly post them.”

In response, she received a form letter saying, “Thank you for contacting the Attorney General’s office. The Governor’s Office of Constituent Services is the agency with the oversight of this matter. You may want to contact them for further assistance.”

WGBH asked for a clarification from the AG’s office, which declined to comment.

Yvonne Rosmarin, an Arlington attorney who has been practicing consumer law for 25 years, says Massachusetts has very particular rules about how goods and services should be priced. But these rules, she said, are specifically written for private companies, not the state.

“If a private company did this, it would be a clear violation of the Massachusetts Consumer Protection Statute,” Rosmarin said.

“There should be sufficient notice of how much you’re going to be charged, when and where it starts, so drivers can choose an alternative route if you don’t want to pay it,” she continued. “And there’s a clear lack of notice here. If you were going to use any other public space that would otherwise appear to be free, for instance a boat landing or a park, you wouldn’t expect to find out weeks later that you’re being charged for its use. And if you don’t have a sign, the road looks like a free road.”

In a statement, a Department of Transportation spokesman said, “the department encourages all members of the public to devote their full attention to the roadway ahead,” and “to make informed decisions so that they are aware of any toll charges they may incur.”

The spokesman also said some larger signs were installed, including a banner with the word “toll” at the Ted Williams Tunnel, though he didn’t say in which direction. And he said narrow walls and high medians kept them from installing signs at some toll gantries.

To see for ourselves, WGBH’s Robin Washington joined Tsapatsaris for her commute home, specifically looking for signs.

Tsapatsaris saw one at the Allston-Brighton toll. “OK. Toll — Oh!” she said, reading the sign. ‘Two axle.’ It says a dollar. That was not here [before].”

It was, however, the only such sign on her route – even though there are three tolls.