A special report by the Office for National Statistics has found there were an estimated 148,800 British citizens living in France in 2016.
Most of these live in Nouvelle-Aquitaine, which includes the Dordogne.
In the UK, there were 154,800 French citizens estimated to be resident in 2013 to 2015, the majority of them working.
About half of British citizens in France were working - the majority of those aged under 50 years old.
The ONS says the Brexit vote has increased the need for data about the people who may be most likely to be affected by the UK's decision to leave the EU and this report is the third in that series.
It said that "unfortunately", information on the occupations and industries of British citizens in France was not available, although it did establish that most of those aged 50 and over were neither working nor looking for work.
Among the 25-to-54-year-old age group, living close to Paris is most common. Its Ile-de-France region is home to 10,400 British citizens in this age group.
The ONS report backs up two commonly held beliefs, that the British like to retire to the Dordogne and that most of the French that come here to live and work are bankers.
The financial sector employs 29% of the French who are working, with the next highest employment sector, 25%, working in public administration, education and health.
The number living here in the UK is far lower than the 300,000 figure that has been generally estimated.
A spokesperson for the French Embassy said it estimated that approximately one out of two French citizens were not registered in the UK, and stressed this was not a requirement.
However, the spokesperson added: "Whatever the numbers, the report confirms the important role that French citizens play in the UK and vice versa, the role that British citizens play in France, hence the need to find a solution for their future status in the framework of Article 50 negotiations between the UK and the European Commission."
The ONS report highlighted the dominance of Spain as a destination for those UK citizens wanting to live abroad.
A previous special report earlier this summer found the population of British citizens resident in Spain was 296,600 in 2016, twice the number choosing France.
But although the numbers of French and British are closely aligned, Spain appears to have no such mutual admiration for the UK, with the ONS saying there were 116,000 Spanish citizens resident in the UK in 2013 to 2015.