UK Special Forces, explained plainly
By Deepak Shukla · Historical account and source-led commentary
United Kingdom Special Forces is the directorate that brings the country's special forces units together. It includes the SAS — 22 SAS regular, 21 SAS and 23 SAS reserve — and the Special Boat Service, the Royal Navy's special forces. Civilians with careers apply to the reserve units; the regular units recruit from serving personnel.
The SAS
22 SAS is the regular Army regiment. 21 SAS and 23 SAS are its reserve counterparts, recruited regionally from people with civilian jobs. If you are reading this while employed and wondering whether it is possible, the reserve units are the route you are asking about.
The SBS
The Special Boat Service is the Royal Navy's special forces element. Different parent service, different specialisms; sits alongside the SAS within United Kingdom Special Forces rather than under it.
What the Army publishes and what it doesn't
Roles, criteria and application routes are published. Operational detail is not, and anyone offering it to you on a forum is guessing, embellishing or lying. Treat the Army's own pages as the only source for current criteria.
Where to start if you're considering it
Attend a briefing event through the official route before you are fit enough. You learn what you are actually training for, and you will start the preparation months earlier than you otherwise would.
A note on accuracy
Entry criteria, standards and selection dates are set by the Army and change over time. Take anything current from the Army's own UK Special Forces Reserve pages; take everything below as one applicant's experience.
What is current policy, and what is my own experience?
I applied to 21 SAS and completed preparatory British Army training in 2015–2016, but did not attempt SAS selection or serve as an SAS operator. My private Georgian training was a separate experience. Military requirements belong to the Army, not to this independent personal website.
Published sources
- British Army Jobs — SAS Reserve role, entry requirements, selection and locations
Primary source for the role and the five publicly described phases; checked 15 October 2026.
- British Army — UK Special Forces Reserve overview and recruiting contact
Official route to the latest unit advice; checked 15 October 2026.
- British Army — 21 and 23 Special Air Service Reserve
Official regiment information; use the Army for current recruitment, not my historical diary.
- Soldier magazine (October 2025) — SAS Reserve recruiting feature
Dated official magazine article. Some eligibility wording differs from the Army Jobs role page; confirm with recruiting.
The Army Jobs listing and the October 2025 Soldier article use different age wording. That is a reason to ask the recruiting unit, not to pick the most convenient figure. These references are checked as of the date above, not monitored automatically.
Get my 21 SAS reserve selection prep guide
What the stages are, what I was training to before I applied, and how I'd build the twelve weeks before a selection weekend. Written from my own application, free, no pitch.