Door-to-door mail delivery is about as American as apple pie. With the Postal Service facing billions of dollars in annual losses, that tradition could be virtually phased out by 2022 under a proposal in Congress.

The House Oversight and Government Reform Committee on Wednesday approved a plan to move to cluster box and curbside delivery, which includes mailboxes at the end of driveways.

The proposal is part of broader legislation by Rep. Darrell Issa, R-Calif., chairman of the oversight and government reform panel, designed to cut costs at the cash-strapped agency by up to $4.5 billion a year. The Postal Service had a $16 billion loss last year.

The bill was approved on a party-line vote, with 22 Republicans supporting it and 17 Democrats opposing it.

Postal Service spokesman David Partenheimer said the agency would evaluate Issa’s bill based on whether it would enable the agency to make $20 billion in savings by 2017.

“The Postal Service looks forward to working with Chairman Issa and the committee to improve the bill as it makes its way through the legislative process,” Partenheimer said.

The agency has been moving toward curbside and cluster box delivery in new residential developments since the 1970s. The Postal Service in April began deciding whether to provide such delivery for people moving into newly built homes rather than letting the developers decide.

“A balanced approach to saving the Postal Service means allowing USPS to adapt to America’s changing use of mail,” Issa said. “Done right, these reforms can improve the customer experience through a more efficient Postal Service.”

About 1 in 3 mail customers has door-to-door delivery, Issa said. The shift would include safe and secure cluster box delivery areas, he said, especially for elderly customers who receive Social Security checks and prescriptions through the mail.

About 30 million residential addresses receive delivery to boxes at the door or a mail slot. Another 87 million residential addresses receive curbside or cluster box delivery.

The cost differences are clear. Curbside delivery costs average $224 per year for each address, while cluster box delivery averages $160. Door-to-door delivery costs the agency about $350 per year, on average.

Sue Brennan, a Postal Service spokeswoman, said, “While converting delivery away from the door to curb or centralized delivery would allow the Postal Service to deliver mail to more addresses in less time, doing so is not included in our five-year plan.”

Brennan said the agency’s five-year plan does call for shifting 20 percent of business address deliveries from door-to-door to curbside and cluster box delivery through 2016.

Rep. Steve Lynch, D-Mass., said the plan to move some 30 million residential addresses from to-the-door to curbside and cluster box service would be virtually impossible in dense urban areas such as his hometown of South Boston crowded with triple-deckers — three apartments stacked on top of each other.

“You’d have to knock houses down in my neighborhood to build cluster boxes,” Lynch said. “This will not work.”

It might work in places like Manhattan with big apartment buildings, he said.

“Look, there’s no availability for cluster boxes in many communities around the country,” Lynch said.

Issa’s plan allows for people with physical hardships to get waivers allowing them to keep door delivery. There’s also a provision giving people the option to keep door delivery by paying a special fee to cover the additional cost.

Issa’s bill also allows the Postal Service to take into account factors such as poverty rates and population density in deciding which areas would be allowed to keep door delivery.