Net migration equals a city the size of Cardiff

Published: 7th Oct 2016

In brief


Immigration adds a city the size of Cardiff to the UK’s population every year.


Net migration in the UK was 327,000 in the year to March. Cardiff has a population of 357,000. But this isn’t true every year. In 2014 net migration was 243,000.

“We’re adding to the population of this country at the minute, the United Kingdom that is, a city the size of Cardiff every year from immigration alone.”

Neil Hamilton AM, 6 October 2016

Net migration was 327,000 people for the year ending March 2016. This is the estimated increase in the overall population of the UK when you compare the number of people coming to live in the UK and the number going abroad.

That’s almost as many people as live in Cardiff. The population there was 357,000 in mid-2015.

This is a type of claim we’ve seen before and there are several towns and cities that could be used for comparison: Wakefield, where the population is around 334,000, Belfast where it’s 339,000 or Wigan where it’s 322,000.

But net migration isn’t at this level every year. It’s been increasing and has been at roughly record levels since 2015.

In 2014 net migration was around 243,000 people, or roughly a population the size of Swansea or Salford.

There is a large margin of error in these migration figures as the number is estimated from surveys taken at the main air and sea ports and routes into the UK.

This factcheck is part of a roundup of BBC Question Time. Read the roundup.

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