The Felixstowe Spa Pavilion will close after the final performance of Aladdin on Sunday night.
The council ended its subsidy and a buyer has not yet come forward.
Manager Julie Howes said she "hoped it wouldn't come to this" but it was a credit to staff that they wanted to see it through to the end.
"They've all given so much to this venue and they wanted to be here right until the last day," she added.
"They really are a superb bunch of people."
Without the Â£250,000 subsidy from Suffolk Coastal District Council, the theatre could not carry on.
Geoff Holdcroft, cabinet member for leisure, said it conducted a review in October 2011 and decided it did not have the money to support the Spa Pavilion in its current format.
"They've got 35,000 people coming though the doors in a year, that compares to 90,000 in Cromer, 160,00 at the Regent in Ipswich," he said.
"It just doesn't compare."
The Spa Pavilion opened in June 1909, with flags put up around Felixstowe to celebrate the opening of a new venue for the east coast.
Folk musician Charlie Landsborough, who has performed at the theatre many times, said it would be sadly missed.
"I'm as sick as everyone else,"  he said. "It was always a place we always looked forward to playing, the staff there were fantastic.
"The theatre had a great ethos about it and we always got a good crowd."
It has also hosted several theatre shows for BBC Radio Suffolk.
All 43 staff have been made redundant.
The final show is the 47th pantomime staged at the venue by the Dennis Lowe Theatre Company - named after its founder who died in 1999.
Suzie Lowe, his daughter and current director of the company, told the BBC in December that the show would ensure the theatre "went out with a bang".
The curtain will come down for the final time later on a 100-year-old Suffolk theatre staging its last production.