Frequently Asked Questions

Enter one or more words to search through our frequently asked questions

or select one of the categories to see all questions and answers for that category


For a naturalisation application, do I need CSI only for the past 5 years?

STOP PRESS - See this FAQ for important information on Comprehensive Sickness Insurance.

Recent developments will likely affect many areas including nationality, naturalisation, registration, access to benefits and more. The answer given below is therefore now out of date.

In the meantime, if you believe you are affected, please seek legal advice. If you have suffered loss because of past decisions where the Home Office said you did not meet the CSI requirement, please email us at .


Naturalisation applications will request 5 years of residency evidence (unless you are married or in a civil partnership with a British citizen, in which case it is 3 years). However, the Home Office can go back 10 years to check whether you fit the ‘good character requirement’ by being lawfully resident in the UK. EU law applies and under EU law, an EU student or self-sufficient person is lawfully resident if they hold Comprehensive Sickness Insurance (CSI). You can watch a video explanation on this topic here:

the3million has a separate citizenship Q&A document, with more extensive information on the CSI requirement: