The polling expert believes this means the election is just under 18 months away.
“It’s October and it’s to do with inflation figures,” he told Sky News. “Because any opinion poll shows the cost of living, the economy, is the top issue.
“Immigration, NHS, these sorts of things come further down the line. Cost of living is not just the goods that you buy in the supermarket, but it’s also the interest rates that people pay in terms of their mortgage.
“And at the local elections there’s a fair amount of evidence that actually it was the people who’ve just faced interest rate increases on their mortgage who didn’t go out and vote for the Conservatives as they have previously said they would.
“Those interest rates have to come down. That takes time. It’s going to be October next year.”
The rate of inflation fell sharply in April, sparking some hope that the worst of the cost of living crisis may be starting to ease.
Figures released on Wednesday show that the Consumer Price Index (CPI) – the headline measure of inflation – dropped to 8.7 per cent in April from 10.1 per cent in March.
But food prices are still surging at 19.1 per cent, according to data from the Office for National Statistics (ONS).
It comes as Labour continued to maintain a significant lead over the Conservatives in opinion polls.
According to a YouGov survey released on Wednesday Labour would gain 23 MPs in Scotland if the election were held tomorrow, and the SNP would fall back to 27 seats.
Since 2010 the Scottish Nationalists have won more than 30 seats at every election contest, and Labour has not surpassed seven in the country.
However, the Ipsos survey was not all good news for the Labour leader as his party’s headline voting intention lead over the Tories is closing.
Labour is still 16 points ahead, but this is down from 23 points in March.