Dear Tripped Up,

On Oct. 3, 2022, I reserved a seat in a Megabus coach for the busy Sunday after Thanksgiving to return to Boston after visiting family in Philadelphia. With a $3.99 booking fee, the total came to $53.98. On Oct. 26, I received an email from Megabus canceling the trip “due to a schedule alteration,” and promising a refund. But I only received $49.99. I wrote every few months demanding my $3.99 back, receiving no response until nearly a year later, when an agent named Danielle wrote back to explain that the service fee was nonrefundable. I understand why a company would keep a fee if I had canceled or rebooked, but this was their decision. Can you help? Gabriel, Boston

Dear Gabriel,

This may be small potatoes compared with typical Tripped Up fare, but no one likes getting nickeled and dimed and $3.99-ed with fees that seem arbitrarily designed to pad companies’ bottom lines. In this maddening case, you didn’t even get the service you paid for and still paid the service fee. Considering the effort you put into this sub-$4 quest, I suspect you care more about the principle than the money.

When I reached out to Megabus, Meghan O’Hare, a spokeswoman for Megabus and its parent company, Coach USA, was unwilling to discuss your request or return the service fee. “Unfortunately, we do not comment on the details of interactions with customers,” she wrote in an email.

Luckily, we have the details, thanks to the mostly one-way email string you forwarded to me. After you sent four emails between November 2022 and September 2023, you finally received a response from Megabus on Sept. 22, one day after you threatened “to file a formal complaint” with the U.S. Department of Transportation. (Good move!)

“The $3.99 booking fee is a nonrefundable charge that is associated with completing a booking that you agreed to by accepting our terms and conditions on our website,” wrote Danielle, a member of the customer-support team. “Unfortunately, that amount won’t be added when totaling the value toward refunds.”

When I wrote back to Ms. O’Hare to confirm this was company policy and to ask what the service fee actually went toward, she did not respond.

You did not end up filing a complaint with the Transportation Department, because when you got in touch with the agency, an official there pointed you to federal regulations that do not appear to require the return of fees for canceled intercity bus trips. (The Biden administration’s recent announcement that it would require airlines and travel agents to disclose fees “the first time that fare and schedule information is provided” do not apply to bus trips. Megabus and its competitors add fees late in the booking process.)

So that leaves us with only Megabus’s terms and conditions, which mention a “$3.99 nonrefundable booking fee” levied “to cover administration charges related to your reservation,” and note that if a customer changes a reservation, this fee is not returned and, in fact, charged again. There is no mention of what happens to the fee if the company itself cancels a trip.

Jeff Sovern, a professor of consumer protection law at the University of Maryland, Baltimore, told me in an email that if “the contract is ambiguous, the ambiguity is construed to benefit the party that accepted the contract — here, the consumer.” But, he added, “I don’t know if a court would buy that interpretation.” And taking Megabus to court for $3.99 might nudge your already quirky quest into tilting-at-windmills territory.

Chris Elliott, the consumer advocate who has helped many travelers through his nonprofit, Elliott Advocacy, suggested a simpler solution for consumers in a similar situation: a credit card chargeback. “Banks take a dim view of these kind of shenanigans,” he wrote. (Since chargebacks usually have to be initiated in 60 to 120 days, this advice applies more to others than to you.)

So why would Megabus keep an administrative fee when it has inconvenienced a customer by not providing a service?

I suppose you could argue that it did incur some costs to schedule the route in the first place and, perhaps, by processing your credit card order. But it’s hard to see how that’s your problem.

Even companies whose business model revolves around booking fees often promise to return those fees if a service is not provided. Both Ticketmaster and Broadway.com specify in their terms and conditions that they refund those fees if a concert or event or show is canceled.

At least two of Megabus’s major competitors do return service fees. Flixbus, which owns Greyhound, provides “the full amount of the ticket fare(s), including any fees,” according to its terms and conditions.

Trailways’ terms and conditions are vaguer. But Alex Berardi, the president of Trailways.com (Trailways’ ticketing and sales platform) told me that when a trip is canceled through no fault of the passengers, “We’re going to get them that money back and that includes the fee.”

“It’s just good customer service,” he said, adding that fewer than 0.75 percent of trips by Trailways carriers are canceled, more than half of those because of weather.

Mr. Berardi also noted that through an agreement between the two companies, you can book Megabus seats on Trailways.com and be protected by Trailways terms and conditions.

Amtrak, in case you are wondering, does not charge a booking fee. And no need to dive into the airlines’ labyrinthine conditions of carriage, since the Transportation Department clearly requires them to refund “the ticket price and/or associated fees” when they cancel a flight.

Guess who else returns service fees? Megabus in Britain. The company, which has been under different ownership since 2019, refunds “the fare and transaction fees,” if it cannot provide suitable alternative transportation, according to its terms and conditions.

Gabriel, you told me that prices had gone up for bus and train fares from Philadelphia to Boston by the time Megabus canceled your trip.

Luckily, thanks to a flexible work schedule, you were able to leave on Tuesday and fly back from Philadelphia on a JetBlue flight you booked with 5,000 miles (worth about $65, according to a 2022 Points Guy valuation), and a $5.60 fee. Total that up, tack on the lost $3.99 Megabus fee, and you ended up out somewhere around $25.

If you are anything like me, you easily made up for your losses with Thanksgiving leftovers consumed at your relatives’ house Sunday through Tuesday. So they’re the ones that should really be mad at Megabus.

If you need advice about a best-laid travel plan that went awry, send an email to [email protected].

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