There are four main ways that people can be removed from the UK: ‘enforced removal’, ‘deportation’ (a particular type of enforced removal), ‘refused entry at port’ and ‘voluntary departure’.
‘Enforced removals’ happen where someone has broken immigration laws and can’t legally remain in the UK.
‘Deportation’ is a type of enforced removal that happens when a foreign national offender has committed a criminal offence punishable by prison and a court has recommended they be deported. It can also happen to people whose removal is considered to be ‘in the public interest’.
‘Refused entry at port’ means a person never actually steps on UK soil and is turned back at the point of crossing the border.
‘Voluntary departures’ don’t necessarily involve someone wanting to leave the UK but it means they have taken steps to arrange it. The figures tell us how many people request the Home Office’s help in departing, and how many ended up leaving the UK without officially informing the immigration authorities.
Figures for deportation aren’t published by the Home Office, although these can be extracted using Freedom of Information requests. Data on other types of removal is published as Home Office immigration statistics.
Some people may be detained while the government establishes whether they have a right to remain in the UK. It might happen, for instance, when the authorities need to establish someone’s identity or where there’s a risk they might evade removal.
Figures for the number of people in detention, entering detention within a given time period, and being removed from the UK are all published as part of the Home Office immigration statistics. This data is released every three months.
It only includes people detained under the Immigration Act, so disregards those detained for criminal reasons. It also doesn’t track people held for under 24 hours at short-term holding facilities.
Child detention figures are available from the same place.
There is information on how successfully the UK Border Agency is managing the UK’s immigration system on the UKBA website. The assessment of its performance includes data on the cost per case ‘processed’, the tax revenue saved by targeting illegality, and the value of drug seizures.
The Home Office has published a list of all policy changes since the 1980s that have had an impact on migration (with dates, policy details, and which aspects of the immigration system they’re considered to affect).