- The UK immigration detention estate is one of the largest in Europe. From 2009 until the end of 2015, between 2,500 and 3,500 migrants have been in detention at any given time.
- In 2015 32,400 people entered immigration detention compared to approximately 30,400 in 2014.
- The majority of immigration detainees are held for less than two months.
- The single most common category of immigration detainees is people who have sought asylum in the UK at some point.
- Over 1,000 children were detained for the purpose of immigration control in 2009, and this number was reduced to just under 130 in 2011. It rose to 242 in 2012, before falling to 128 in 2014 and 2015.
- In late 2015 the estimated average cost of detention was £91 per day.