The UK’s population will peak more than 40 years earlier than previously thought, official projections show. 

The Office for National Statistics (ONS) calculated the number of people living in the country will hit a high of 72.5million in 2054, and then begin to fall. Its previous estimates suggested the UK peak would not arrive until 2096. 

Within that UK-wide total, changes in the ONS’s calculations mean it now expects the first ever peak - and decline - in England’s population. 

Previous sets of data compiled by the official statistics body had forecast that the number of people living in England would continue to increase for at least the next century. 

But now it is forecasting that the population will hit its highest point of just over 72million in 2054, before beginning to fall. 

For other nations in the UK, their predicted population peaks have been brought forward. The ONS expects Wales’ population to peak in 2035, rather than in 2077. 

Scotland’s population meanwhile will reach its highest level just seven years from now, in 2033, rather than in 2051 as previously estimated. And Northern Ireland’s population will peak two years earlier in 2031. 

The changes are due to a combination of slowing net migration and births outnumbering deaths. 

The projections set out how the UK population is set to grow more slowly than previously thought over the next few years. 

It is forecast to climb from 69.3million in 2024 to 71million in 2034 - 1.2million lower than previously forecast. The decline is mainly due to a significant dip in net migration. 

The Conservative government introduced a number of changes to visa rules which began to be implemented in spring 2024, leading to a sharp fall in net migration - the difference between immigrants arriving here and those emigrating. 

The ONS said it was assuming net migration would continue at 230,000 a year, down from the 340,000 a year figure used in its previous calculations. 

The ONS forecast 7.3million immigrants will come to the UK in the ten years before 2034, including returning Britons, and that there will be emigration of just over 5million, leaving net migration at 2.2million over the decade. 

The ONS reported that net migration will remain the only source of population growth. 

According to the most recent data, asylum seekers - including small boat migrants - now make up 44 per cent of net migration. 

If asylum claims continue at a similar or higher rate it would see it playing an ever-growing role in Britain’s starkly changing demographics. 

Shadow Home Secretary Chris Philp said: ‘This is a catastrophic projection. 

‘Mass immigration undermines our society and low wage immigration is bad for the economy. 

‘Labour have opened the door without any plan to deal with the consequences, and the ONS shows this will continue to impact us into the 2030s.’ 

Home Secretary Shabana Mahmood has set out plans to double to ten years the time most migrants have to wait to qualify for ‘indefinite leave to remain’ in Britain, with separate measures making refugee status temporary rather than permanent. 

However, it remains unclear whether opposition from within the Labour Party will lead to the proposals being watered down.