A petition to save Ditchling Post Office has attracted 1,700 signatures.
Residents were concerned the Post Office would be moved into a shop rather than have its own High Street presence.
It was confirmed the facility would stay but the Post Office said it would review the decision in September 2015.
Lewes MP Norman Baker said: “This is good news for Ditchling and I hope it will put people’s minds at rest.
“There has been a good community effort supported by elected representatives including myself, councillor Tom Jones and the parish council.”
Cllr Tom Jones, who represents Ditchling on Lewes District Council, said postmaster David Holmes had put up a ‘strong financial case’.
However he described plans for a review as a ‘sting in the tail’ and described the news as ‘short term security’.
The village amenity will be kept as a Community Post Office – awarded when there are no suitable retailers who could operate a Post Office branch within half a mile.
Postmaster David Holmes heard the village service could become a Post Office Local, which operates out of other shops rather than having its own high street presence.
Campaigners said this change would have a ‘profound effect’ on customers.
Mr Holmes said: “I am delighted that the Post Office in Ditchling has been designated as a Community Branch Post Office.
“I have been overwhelmed by the huge support from the local community, in the form of a petition of over 1,700 signatures as well as 246 signed online and 841 Facebook likes.
“I would like to take this opportunity to thank everybody who has helped.”
The Post Office was considering changing the village Post Office in Lewes Road into a Post Office Local, which would have meant many of the services, such as accepting cash deposits into bank accounts, payment of bills without a bar code or accepting cheques for payments, would no longer have been available in the village, impacting on the elderly and those without cars.