More than 2.2million immigrants arrived in the UK between 2001 and 2005, figures showed.
Over the same period 870,000 foreign-born people left the country, which meant that the foreign-born resident population grew by 1.4million in a five-year period — by far the fastest rate of growth in history.
At the same time, the UK-born resident population fell by half a million, with 897,000 leaving the country for a year or more and 394,000 returning.
One in 10 of the population was now foreign-born, compared to eight per cent in 2001.
The figures were published by the Office for National Statistics in a report to a House of Lords inquiry into the accuracy of migration data.
They showed that migrants added 939,000 to the UK’s population in the five years to last summer — an extra 515 people every day.
The overseas-born population of working age increased by 26 per cent to 947,000, while the British-born working population fell by 44,000.
About 40 per cent of long-term migrants to the UK in 2005 were aged 15 to 24, compared to 13 per cent for the UK population as a whole.
The ONS recently revised upwards by one third its assumptions for future immigration from 145,000 to 190,000 a year.
David Davis, the shadow home secretary, said: “This is yet more evidence showing the real need for a limit on non-EU migrants coming to the UK.
Only by doing this can we control immigration.”