Pompey Supporters’ Trust money will give more money to Balram Chainrai as part of its takeover of Fratton Park.
The club’s former owner will get £125,000 during the season 2015/16 and the same amount again the season after.
He has already been given £3.1m.
The News understands that an extra £2m could switch hands if Pompey make it back to the Premier League in the next 10 years.
But Mick Williams, trust board member, said fans shouldn’t be alarmed.
‘They shouldn’t be concerned, it’s just part of the purchase price,’ he said.
‘No-one from any of the old owners has any hold over the club.
Pompey chairman Iain McInnes said: ‘We have to match the confidence that everyone has put in us.
‘As far as governance goes, it’s going to be different to anything that was going on before.’