A growing number of city and town offices in Maine plan to open on Dec. 29, a Saturday, to issue marriage licenses on the first day same-sex marriage is legal in the state.

The extended hours will come at a price, but the extra payroll costs are expected to be offset by increased revenue from the licenses.

On Monday, Falmouth became the latest community to announce special hours. The town, like the city of Portland, will open its office at 12:01 a.m. on Dec. 29 to be among the first to issue licenses and host same-sex weddings.

“These people have been waiting so long to be able to do this,” said Town Clerk Ellen Planer. “I’m honored to be able to offer it to them as soon as it’s available.”

Other towns and cities plan to open their offices at 9 a.m. or later on Dec. 29.

Augusta City Manager Bill Bridgeo said the city decided to open on Dec. 29 after several residents called his office last week to find out whether the city could accommodate couples who want to marry on that day.

Bridgeo said he and his staff talked briefly and decided they could open from 9 a.m. to noon.

City Clerk Barbara Wardwell, who offered to work, is salaried so there will be no extra cost to the city. One other staff person plans to work, for three hours at overtime pay, Bridgeo said.

The relatively small extra cost of opening the office for three hours on Dec. 29 likely will be made up by the revenue from the $40 marriage licenses.

“Given the significance of this, a small amount of public money wasn’t an issue of concern,” he said.

More and more communities are announcing plans to hold Saturday hours on Dec. 29. Augusta was the first to announce, followed by Gardiner, Hallowell, Brunswick, Portland and Falmouth.

Town and city officials say the decision is being made to offer a public service, not for financial reasons.

Fran Smith, town clerk in Brunswick, said two staff people will work from 9 a.m. to noon on Dec. 29 to issue licenses.

“We are asking people to make appointments,” she said. “At this point, we don’t know what the demand will be, but we thought it was the right thing to do for residents.”

Smith said the extra revenue generated on that day will likely cover the cost of opening the town office.

Bigger cities, including Portland, are likely to incur more cost by opening early, but they’re also likely to do more business.

Portland announced last week that it will open its office from 12:01 a.m. to 3:01 a.m. Spokeswoman Nicole Clegg said the city probably won’t know exactly what the extra cost will be until after that day, but she estimated it at $600 for three hours.

It will take only a handful of weddings to cover that, with license fees of $40 and marriage ceremonies costing $125, she said.

Augusta manager Bridgeo said people may see Saturday hours as an anomaly but he and his staff often work outside of normal business hours, depending on the circumstances.

On a Memorial Day several years ago, for instance, Bridgeo went into the office to fax a birth certificate to a resident who was stranded at the airport in Philadelphia and didn’t have his passport for a flight to Belize.

Clegg, too, said there is precedent for opening city offices outside of normal hours, most recently for voter registration.

Municipalities that plan Saturday hours on Dec. 29 have made it clear that heterosexual couples will also be issued licenses if they show up.

“And if people want a dog license, we’ll accommodate that, too,” Bridgeo said.

Planer, Falmouth’s town clerk, said the town office will open at 12:01 a.m. on Dec. 29 by appointment only, and will open at noon that day for couples who prefer exchanging vows during daylight hours.

Portland Mayor Michael Brennan said Monday that the city’s plan to offer marriage licenses the minute gay couples could get them was driven by the historic nature of the law, not a desire to be the first.

“If we’re first that’s great, and if we’re not, congratulations for whoever is able to be first,” Brennan said.

Interest in same-sex weddings in Maine has been building since voters approved a citizens initiative Nov. 6 to make them legal.

It intensified last week when the state announced that couples would be able to get married earlier than previously anticipated because the approval process had been quicker than expected.

There are conditions for getting a marriage license: At least one person in the couple must live in the city or town where they seek a license, and they must provide proof of residency.

Portland Press Herald Staff Writer Matt Byrne contributed to this report.