The cost of the weekly shop will rise by almost 3% if Britain left the EU, David Cameron has said.
Writing in The Sun on Sunday, the Prime Minister claims a vote to leave would mean the average family shelling out an extra £120 a year on food and drink.
Clothes and shoes would also see a price hike of 5% and he questioned whether the increases were "worth it".
"Every credible economic organisation" - including the Bank of England and the International Monetary Fund - believes Britain will be better off inside the bloc, he said.
Outlining the economic consequences for families in the event of a leave vote in the June 23 referendum, Mr Cameron said that the growth of wages would slow.
"It's yet more evidence that the outcome of this referendum will have real and direct consequences for every family in Britain," he said.
He also said leaving the union would see many of the three million jobs linked to trade with Europe put at risk.
The Conservative leader said that those in work are now seeing wages grow above inflation, thanks to the strong economic recovery since the financial crash.
He said: "Are we really going to chuck this all away? Why would we want to do this to ourselves, just as our economy is predicted to grow so strongly if we remain?"
Speaking directly to voters he added: "The evidence is clear: leaving the EU carries serious risks - to your job, to your wages, to the economic security that families rightly prize above all else."