A major analysis by the University of Oxford estimates the population of England has risen by 565,000 since 2011 due to immigration.
The figures suggest the migrant population of every local authority in the country may have risen.
Two-thirds of the rise is attributed to people from the European Union.
The Migration Observatory unit says it came up with the projections because similar official data will not be available before the general election.
Official estimates for migration focus on movements of people in and out of the UK - and national statistics only definitely record the population and where it comes from every 10 years at the national census. The latest estimate for how many migrants have settled will not be available until later this summer.
Taking two key measures of people in the UK - the 2011 census and rolling data from the Labour Force Survey - Oxford has projected that immigration has added to the population right across England as the economy has expanded.
Its analysis suggests the greatest change has been in London. Almost 3.2 million people in the capital are now born abroad - 200,000 more than at the time of the last census.
The foreign-born population of the South East is projected to have also risen to more than 1.1 million.
Migration estimates from Oxford University
Official estimates do not reveal where migrant groups of different origins have settled in the UK over the past three years - but the Migration Observatory has projected what it thinks is going on for each region and local authority.
It has broken down local figures to create an online map projecting where migrants have come from.
Areas which have experienced rapid growth since Eastern European nations joined the EU in 2004 have continued to see those communities grow - particularly in the agricultural areas of the east of England.
There, Oxford estimates that the EU-born population is almost a quarter of a million - about 12% higher than at the time of the 2011 census.
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BBC News - Population rose 565,000 since 2011 - Oxford analysis