BODMIN residents will have to travel to Lanivet or Wadebridge to use Post Office services when the town's branch closes for almost two weeks.
The branch within the Costcutter store in Fore Street will be refurbished before reopening as an open-plan post office with extended hours, including offering some services on Sundays.
The revamp means the Post Office area of the shop will be closed from February 24 until March 7.
Post Office Ltd says the move is part of its plans to modernise the network and extend opening hours, and the refurbished Bodmin post office will have five serving positions.
There will also be a serving point at the retail counter which will be available for most Post Office transactions throughout shop opening hours.
It says customers will benefit from opening hours being extended, with selected products and services available during shop opening hours, which will be Monday to Sunday from 8am to 10pm.
The extra hours will include Saturday afternoon and all day Sunday. The branch will also open earlier and close later.
There was support for the move from at least one customer; Jon Hancock, who lives in College Green, said: " I don't know about people on benefits, as that doesn't affect me, but I'm quite prepared to travel to Lanivet to use the post office there if it means a better service with longer opening hours at the Bodmin branch."
Bodmin Chamber of Commerce chairman Chris Wilkes said the temporary closure would not inconvenience traders too much.
"Most traders tend to do their transactions through their banks," said Mr Wilkes. "Perhaps there may have been a case for keeping at least one workstation open, but extended opening hours will be good news for everyone in the town."
Post Office area manager Adrian Skinner said: "We understand how important post office services are to the people of Bodmin and we're confident that this new, modern post office service will meet the needs of the local community and secure services for the future.
"The modernisation is part of a major investment programme to convert the post office network to new-style branches and this investment, the largest in the history of the Post Office, marks a commitment to no more branch closure programmes," he said.
North Cornwall MP Dan Rogerson said he welcomed the revamp.
"The refurbishment will make it easier for people to use the post office and will help to secure the future of a branch in the town centre," he said. "The upgrade will also mean that some post office services will be available from the shop counters, which are open until 10pm, after the main post office closes at 5.30pm."