Detention Centres

The network of immigration detention centres around the country, often known as the ‘detention estate’, is made up of Immigration Removal Centres (IRCs) and Short Term Holding Facilities (STHFs).

People can be held at residential STHFs for up to seven days before being removed from the UK, released, or moved to an IRC. People detained at IRCs can be held indefinitely. People can also be held under immigration powers in prisons.

In 2022, 95% of people in detention were ultimately released. 78% of all individuals held in detention during that year were released on bail, and 73% were released after fewer than 28 days. High release rates indicate that, in many instances, the initial act of detention was unwarranted and unnecessary.

Detention Action supports people being held in Colnbrook and Harmondsworth IRCs near Heathrow airport and people held under immigration powers in prisons.


People often have deportation proceedings brought against them following prison sentences. Many of these people are then kept in prison indefinitely under immigration powers following the end of their sentences.

People held in prison are being held under the same powers as people in IRCs, but they find it difficult to access the support and services to which they are entitled. For example, they are not allowed mobile phones, visiting may be harder, they do not have access to legal surgeries, and lack access to vulnerability screenings (Rule 35) that apply in IRCs.

Other IRCs

For information on visiting and support groups for detention centres around the country, see AVID’s website.