21 SAS reserve selection process: where each stage fits
By Deepak Shukla · Historical account and source-led commentary · Updated
The Army Jobs SAS Reserve role page, checked 15 October 2026, describes five stages: a briefing course, aptitude, a standard operating procedures and tactics course, surveillance/reconnaissance and SERE training, and continuation training. These follow required Army training and experience; they are not a stage-by-stage description of my historical pathway. I applied to 21 SAS, completed Alpha and Bravo, attended around 10–15 Wednesday evening preparation sessions and a 21 SAS-linked assessment weekend where our performance was monitored. I later chose not to continue to the formal selection course; I did not qualify or serve as a member of the Regiment.
2026 retrospective clarification · 17 October 2026
I recall applying around autumn 2014, aged 28, with Army training following in 2015–2016. The regular Wednesday evenings were connected with preparing applicants for selection; around 10–15 is my approximate recollection, not a verified attendance count. I completed the Army's Alpha and Bravo stages before the later preparatory/assessment weekend involving 21 SAS. At that unit-linked weekend, our actual performance was reviewed and monitored. I subsequently decided not to continue to the later formal SAS Reserve selection course. That decision does not erase the evaluated preparation I had already undertaken.
My two weekends must not be conflated
The later 21 SAS-linked preparatory/assessment weekend was distinct from the earlier, general Army ATC Pirbright assessment weekend described in Part 2. I am not assigning an unverified stage name, location, date, score or pass/fail outcome to the unit weekend, or equating it with today's published briefing course.
The stage most internet guides skip: becoming prepared as a soldier
For an applicant entering without prior service, the official Army role description says that basic military training, initial trade training and experience come before attempting selection. This matters because an Army assessment weekend, a recruit-training course and Special Forces selection are not interchangeable events. My 2015 diary about ATC Pirbright is valuable precisely as a description of an early stage; it should not be represented as an account of completing selection.
Stage one: the briefing course
The Army Jobs page calls this a six-day briefing and assessment. It is intended both to explain what lies ahead and to assess an applicant's suitability for progression. An applicant should treat current timings, fitness measures and entry conditions as information to obtain from the recruiting team. My own notes were written years before the present description, so I do not try to map every day of my historical application onto today's published timetable.
Stage two: aptitude
The official public summary describes a continuous period of assessed physical and mental resilience, including progressive timed marches. Its importance is obvious without reproducing test timings or tactical details from unofficial forums: the Army is assessing suitability for a demanding military role, not simply a runner's personal best. Do not use old race reports as a proxy for a military assessment.
Stage three: standard operating procedures and tactics
After aptitude, the Army's published description identifies a further course requiring people to learn and apply military skills under pressure. It is enough for a public guide to name this part of the pathway and point to the official source. Describing technical content I never trained in would add false authority and do applicants no favour.
Stage four: surveillance, reconnaissance and SERE
The Army publicly names surveillance, reconnaissance, signals and SERE as a subsequent training touchpoint. Those are the terms in its recruiting material. I am not reproducing methods, operational details or supposed insider tips, and I cannot independently verify the arrangements for an individual intake.
Stage five: continuation training
The published pathway ends with continuation training, intended to develop the capabilities of a deployable SAS Reserve soldier. Finishing an early Army course does not put a person at this point. After Wednesday preparation sessions and the later monitored unit weekend, I chose not to continue to the formal selection course; I do not claim continuation training or service as a member of the Regiment.
How long does all this take?
A useful question is how much time to allow for initial Army training, applications, preparation, selection windows and ongoing service—not how quickly somebody can cram through a fixed sequence. Army Jobs includes durations for some stages; these can change and do not cover the entire journey. The October 2025 Soldier recruitment feature discusses a sustained selection commitment. Ask the unit for your pathway and your current availability rather than planning around a number extracted from a blog.
Where my first-hand material is most useful
The application diary, ATC Pirbright account, 2015 Georgian private-training story and June 2016 decision each answer a different historical question. Read them in that order for a candid view of motivation, training and changing priorities. Use the sources below for today's process; contact the military recruiting team for anything that would determine your eligibility or schedule.
What is current policy, and what is my own experience?
I applied to 21 SAS, completed Alpha and Bravo, attended around 10–15 Wednesday evening preparation sessions and a 21 SAS-linked assessment weekend where our performance was monitored. I later chose not to continue to the formal selection course; I did not qualify or serve as a member of the Regiment. My private Georgian training was a separate experience. Military requirements belong to the Army, not to this independent personal website.
2026 retrospective clarification · 17 October 2026. The later unit assessment weekend was distinct from general Army ATC Pirbright assessment. Official-source check dates below are separate from this owner clarification.
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.
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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.