About 200 letters were sent to postal voters in the city using the first class stamps but recipients were asked to pay £2.50 in unpaid postage fees to unknowingly collect Portsmouth Independents Party pamphlets.
Chris Kimber, who lives in the Charles Dickens ward and was among those affected, said the issue had been poorly handled by the party, which has eight candidates standing in Thursday's election.
‘I got a card from the Post Office last week saying I needed to pay £2.50 for a package which had had insufficient postage paid,’ he said. ‘I went out of my way to get it, thinking it was something I was expecting from QA.
‘When I collected it and it turned out to be an election pamphlet I was annoyed to say the least. I wouldn't have given them my money even if I wanted to vote for them.’
After approaching the party to raise the issue he was offered his money back by the party but criticised the 'unprofessional' response.
‘The messages were very poorly written and when I said I wasn't comfortable giving them my bank details over Facebook they just laughed,’ he added.
Party leader George Madgwick, a serving city councillor, said the fake stamps had not been spotted when they were used as part of a group effort to post more than 1,000 letters ahead of the postal voting deadline.
‘They were bought on Amazon,’ he said. ‘The listing had good reviews and as far as we could tell, they were perfectly legitimate. They were even more expensive than they would have been at the Post Office.
‘After we first noticed the issue we noticed there had been complaints in February that they were selling fakes and yet they were not removed.
‘We contacted Amazon and I've been less than impressed with their response.’
The stamps are still listed for sale by the retail giant with a rating of 4.6 stars out of five, although the majority of recent reviews raise issues with their legitimacy.
A spokesman for Amazon said the stamps had now been taken down from its website.
‘The authenticity of products on our store is a top priority,’ they said. ‘We encourage customers with concerns to report them to us so that we can investigate and take action.
‘Fewer than 0.01 per cent of all products sold on Amazon receive a counterfeit complaint but we won’t rest until that number is zero. The product in question has been removed and we have taken action against the seller.’