What is a 21 SAS soldier — and when are you just an applicant?
By Deepak Shukla · Historical account and source-led commentary · Updated
21 SAS, the Artists Rifles, is a Special Air Service Reserve regiment in the British Army. Applying, training with the Army and being selected into the regiment are three different things. I know because my own story ended at preparation: I applied, trained through Alpha and Bravo and later chose not to continue to formal selection. Here's what the different terms mean when you see them in a biography or recruiting guide.
On this page
What 21 SAS refers to
In everyday conversation, people use '21 SAS', '21st SAS', 'SAS 21' and 'SAS Reserves' almost interchangeably. The proper name points to 21 Special Air Service (Artists Rifles), one of the two SAS Reserve regiments alongside 23 SAS. The regular SAS is 22 SAS. These organisational labels matter because applying to a reserve unit is not the same as holding an operational role within it.
An enquiry or application is not membership
At the first stage you can be a civilian considering recruitment, an applicant completing ordinary Army checks, or a soldier developing experience in another Army Reserve unit. Those descriptions do not mean you have passed the later reserve selection course. I could say I had applied and trained, but not that I had been selected as an SAS reservist. That boundary matters to anyone writing their own story or reading someone else's.
What distinguishes an SAS reservist
The Army's recruiting material describes 21 and 23 SAS as demanding reserve service commitments that can involve deployments and ongoing training, undertaken alongside civilian careers. Being in the Reserves is not a weekend endurance club or an automatic badge for turning up at an application event. The current Army website is the source for exactly what the job entails and what a successful candidate must complete.
What about an ordinary Army reservist?
The official route can involve basic military training and experience with another Army Reserve unit before being allowed to attempt SAS Reserve selection. A reservist who has completed that earlier training has achieved something different from an SAS Reserve selection pass. This distinction explains why a civilian may be allowed to enquire about 21 SAS while still facing a much longer journey before selection.
Why I am fussy about the words
When you're young, excited and chasing something daunting, it is tempting to wrap the whole chapter in the most impressive label. What I remember most vividly, though, is the routine: Alpha and Bravo, the Wednesday sessions, the assessed preparation weekend and the decision to stop in 2016. That story is stronger without an invented final chapter.
Do 21 and 23 SAS do the same thing?
They are both SAS Reserve regiments, but don't assume that a forum post about one unit or an old selection intake describes your current path. The official Army pages describe common application principles and distinguish the regions where each regiment recruits. Read the 21 vs 23 vs 22 comparison here for the organisational differences, then confirm individual recruitment questions directly.
A separate route exists for specialist support staff
The British Army's official 21/23 SAS page also describes support-squadron roles for already trained serving personnel. It says those support roles do not require passing the same selection as a trooper, but they have their own service, fitness and trade-qualification rules; the Army says they do not accept direct civilian entrants to those support roles. A person working in a support capacity should not be described as a selected SAS trooper, and my own history was neither of those.
If you're considering joining
Ask the official recruiting team which route applies to a civilian or serving applicant, what prior Army training is needed, which stage you would actually be entering and how service commitments fit your life. Those practical answers matter much more than a blog headline or another applicant's past fitness time.
Sources and current requirements
My experience dates from 2014–2016. Eligibility, fitness standards and the selection process change, so for anything current use the Army's own pages:
- British Army Jobs — SAS Reserve role, entry requirements, selection and locations
- British Army — UK Special Forces Reserve overview and recruiting contact
- British Army — 21 and 23 Special Air Service Reserve
- Soldier magazine (October 2025) — SAS Reserve recruiting feature
Rechecked 7 November 2026. The Army Jobs listing and the October 2025 Soldier article use different age wording — ask the recruiting unit rather than picking the convenient figure.
Read next
Get my 21 SAS application and preparation guide
What I actually did during Army preparation, what I learned, and a general twelve-week fitness framework informed by endurance sport. It is not a military selection programme; current standards come from the Army.