Net international migration in the year to mid-2018 was 275,000, which was "broadly in line" with the average of the last five years, the ONS said. Migration has been the main factor pushing the UK population up to 66.4 million , according to the Office for National Statistics , which said it had made a bigger impact than births and deaths . The 0.6 % rate of total growth in 2018 , however , has remained stable for two years now , and is lower than any period since 2004 . ONS figures said the population fell by about 395,400 in the year to March 2018 , with births at 744,000 ( their lowest in 13 years ) deaths at 623,000 and net migration of 275,000 . Environment and Population Matters said the UK figures were unsustainable .
Migration has been the main factor pushing the UK population up to 66.4 million , according to the Office for National Statistics , which said it had made a bigger impact than births and deaths . The 0.6 % rate of total growth in 2018 , however , has remained stable for two years now , and is lower than any period since 2004 . ONS figures said the population fell by about 395,400 in the year to March 2018 , with births at 744,000 ( their lowest in 13 years ) deaths at 623,000 and net migration of 275,000 . Environment and Population Matters said the UK figures were unsustainable .