More British people emigrated in 2003 than at any other time since the 1979s, according to official figures.
Estimates produced by the Office of National Statistics reveal some 190,000 British citizens left in 2003.
Approximately 105,000 British citizens returned in the same year - a net outflow of 85,000 people.
Overall, 151,000 more people of all backgrounds came to the UK than left in 2003, an apparent slight slowdown in the rate of international migration.
In total, 512,000 people came to live in the UK for at least one year while a record 361,600 left.
According to the estimates, produced from surveys of passengers at ports, the slight slowdown in arrivals over departures comes after a decade of growth.
While 151,000 more people arrived than left in 2003, this is lower than the 153,000 in 2002 and the 171,000 in 2001.
The figures estimate all people arriving to live in the UK for at least 12 months and do not detail permission to settle permanently.
They include students and work permit holders, refugees and asylum applicants waiting a decision.
Across all nationalities, more people arrived to live in the UK for at least a year than left, excepting British citizens.
While 106,000 British citizens returned to the UK, 190,900 left - the highest estimated annual departure of British citizens since counting methods were first overhauled in 1991.
This may also represent a record number of departures of British citizens, although it is difficult to confirm due to different counting methods over the years.
The number of non-British citizens who arrived during the year was 236,000 compared with 94,000 in 1994. The number of non-British citizens leaving was 171,000 compared with 113,000 over the same period.
Some 14,000 more people arrived from the old 15-country European Union than left. Some 20,000 more people arrived than left from the old Commonwealth countries of Australia, New Zealand, Canada and South Africa.
For other Commonwealth nations, a record 86,500 more people arrived than left. For all other foreigners, which includes United States citizens, 114,800 more people arrived than left.
Total figures for immigration, published earlier this year, revealed a complex pattern of movements of people.
Almost 140,000 people were allowed to settle permanently in the UK in 2003, a fifth up on 2002. This represents the third year of increased settlement grants, after a fall between 2000 and 2001.
Immigrants given settlement because of work doubled to 29,600. But the number of students and people arriving on work permits declined slightly
However, the majority of settlements (47%) were for family reasons, with 65,800 people allowed to bring wives, husbands or children into the country.
Approximately 15% of those given permanent settlement had formerly been asylum seekers, given either refugee status or exceptional leave to remain.
According to the figures, this year's net outflow of British citizens could be the highest on record. In the early 1970s large numbers of British citizens emigrated, principally to Australia. By 1975 the numbers leaving the UK had reached 168,000 a year, although it then dropped back.
Until the mid 1980s, overall emigration from the UK was higher than immigration.
Since 1998 the annual immigration figure has been over 100,000, reaching 171,000 in 2001 before dropping back again.