WASHINGTON — Passengers love the idea, but airlines hate it. The government wants to require that travelers be told up-front about basic services that are not included in the price of a ticket and how much extra they will cost.
The Transportation Department proposed Wednesday that passengers be provided detailed information on fees for a first checked bag, a second checked bag, advance seat assignments, and carry-on bags.
The rules would apply whether passengers bought tickets on the phone, in person, or online — and not just from airline websites. Airlines that want their tickets to remain available through travel agents and online ticketing services would have to provide them information on fees for basic services, too, something most have been reluctant to do.
The idea is to prevent consumers from being lured by low advertised airfares, only to be surprised later by high fees for services once considered part of the ticket price. Airlines currently are required to disclose only bag fees, and even then they do not have to provide an exact price. Some provide a wide range of possible fees.
‘‘A customer can buy a ticket for $200 and find themselves with a hidden $100 baggage fee, and they might have turned down a $250 ticket with no baggage fee, but the customer was never able to make that choice,’’ Transportation Secretary Anthony Foxx said in an interview.
But adopting the changes would be the wrong choice, said a trade association for the airline industry.
The “proposal overreaches and limits how free markets work,’’ Airlines for America said in a statement. And it predicted ‘‘negative consequences.’’
Under the proposal, fees would have to be specific to the advertised airfare. Any frequent-flier privileges would also have to be factored into the price if the airfare is advertised on an airline website and the passenger supplies identifying information. The proposal would prohibit ‘‘unfair and deceptive’’ practices by airfare search tools, such as ranking flights by some airlines ahead of others without disclosing that bias to consumers.
The rule does not cover fees for early boarding and other services regarded as optional.
The government also wants to expand its definition of a ‘‘ticket agent,’’ so that consumer protection rules also apply to online flight search tools such as Kayak and Google’s Flight Search, even though they do not actually sell tickets. Many consumers are unable to determine the true cost of a ticket because fees are often hard to find, the government says.
‘‘The more you arm the consumer with information, the better the consumer’s position to make choices,’’ said Foxx.
The public has 90 days to comment on the proposal. Foxx said he hopes the rule will become final within the next year.
In the meantime, airlines have taken their case to Congress. A House committee recently approved a bill that would effectively nullify the rule and allow airlines to return to displaying base fares and adding in taxes and fees later.