Question to the Home Office:

To ask the Secretary of State for the Home Department, what the cost to the public purse was of monitoring the MI5 watchlist in the latest period for which data is available.

The Chancellor confirmed in the Spring Statement on 26 March 2025 that the Single Intelligence Account, which provides funding for MI5, SIS and GCHQ, would increase this year to £4.6 billion. Funding for CT Policing, who work closely with MI5, also increased to £1.2 billion this year.

It is a longstanding policy not to discuss the costs and resources associated with specific capabilities such as domestic and international watchlists. Detailed breakdowns of funding allocations for the UK Intelligence Community and CT Policing are not published for security reasons.