The town must resign itself to having a post office in a temporary cabin in Goldsmiths Lane car park for at least 18 months, town clerk Andrew Rogers told town council members.
He praised efforts by post office managers to get the town a permanent new post office when the one in Martin's newsagents in St Martin's Street closes at the end of July.
He said: "They are pulling out all the stops.
"But the reality is that we will have a four-window post office in a temporary building for at least 18 months. A number of permanent sites are being considered and negotiations are proceeding but these could take a long time."
A petition organised by mayor Betty Atkins urging the Post Office to make sure the town does get a permanent replacement has already topped 1,000 signatures and more are being collected.
She said: " We say there must be a continuity of service and that Wallingford should not be without its post office even for one day."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article