The Army Officer Selection Board (AOSB) is a multi-stage assessment designed to evaluate your cognitive ability, personality, and leadership potential for officer roles in the British Army.
The AOSB process consists of two key stages, the AOSB Briefing and the AOSB Main Board, both of which test reasoning, problem-solving, and decision-making under time pressure. The Briefing Stage provides an initial measure of your aptitude, while the Main Board challenges you with complex, rapid-response exercises that mirror the demands of commissioned service.
Thorough AOSB preparation, particularly for the psychometric tests, memory assessment, and personality profiling, is essential to performing at your best across both stages.
Our AOSB Preparation Pack offers realistic practice tests, timed exercises, and personality profiling drills to help you build speed, accuracy, and confidence, giving you the best chance to succeed at both the AOSB Briefing and Main Board, and progress to Sandhurst.
Our AOSB PrepPack is designed to give you complete preparation for the cognitive, memory, and personality sections of the Army Officer Selection Board.
You'll work on the most challenging parts of the AOSB for Briefing and Main Board, and benefit from detailed study guides and video tutorials:
Build speed, accuracy, and confidence with expert-created AOSB psychometric practice tests, targeted drills, study guides, and video tutorials - everything you need to prepare for the Army Officer Selection Board.
The Army Officer Selection Board (AOSB) is the British Army's officer selection process at AOSB Westbury, designed to assess your cognitive ability, personality, leadership potential, and physical readiness. Successful candidates progress to officer training at The Royal Military Academy Sandhurst (RMAS).
The AOSB combines multiple assessment methods in two stages, the AOSB Briefing and the AOSB Main Board.
AOSB assessment includes psychometric tests, personality profiling, cognitive challenges, group exercises, interviews, and physical tasks, all aimed at evaluating how you think, lead, and perform under pressure.
Our AOSB PrepPack focuses on the three sections that benefit most from structured practice.
Here's what each involves:
The AOSB Psychometric Test measures your cognitive ability across verbal, numerical, and abstract reasoning, assessing your problem-solving skills, logical thinking, and ability to work accurately and quickly, all of which are key indicators of potential success as an Army officer.
The mental aptitude test is taken at both the AOSB Briefing and the Main Board. The version at the Main Board is more demanding, so candidates who have already sat the Briefing should not assume prior familiarity is sufficient preparation.
There are three main test sections:
With very limited time per question, careful preparation is essential. The psychometric section tests your speed, accuracy, and reasoning simultaneously under strict time pressure. AOSB psychometric test practice is the most effective way to build the familiarity and confidence needed to perform at your best.
Take a look at an AOSB psychometric test sample question:
This is a sample question from the AOSB Numerical Reasoning section.
In this section, you are presented with five answer options for each question. Calculators are not permitted, as the assessors are looking for candidates’ basic mathematical knowledge and ability. You will need to work quickly to ensure that all questions are answered within the time limit.
To complete the AOSB psychometric section sample question, look at the below dataset and answer the question that follows:
Question: In which of the following years were men exactly half the number of swimmers?
Choose your answer before looking at the explanation below.
The correct answer is 2006.
In this question, we need to find the year when the number of male swimmers is half of the total number of swimmers.
To approach this question, we can estimate by looking at the numbers. If one group (male swimmers) equals half the total number of swimmers, then the sum of the other two groups (female swimmers and any other category) must also equal half of the total number of swimmers. Our task is to find the year when the number of male swimmers is exactly half of the total number.
In 2006, there were 120 swimmers in total, with 60 of them being men, which is exactly half.
⭐️ Golden Tip: Focus on recognising question patterns and applying effective strategies for each reasoning type. You'll be able to build speed and confidence by practising with timed tests that mirror the real AOSB format. Our PrepPack offers realistic verbal, numerical, and abstract reasoning tests, complete with explanations and targeted drills.
The AOSB Main Board Personality Test evaluates how your core traits influence your behaviour, decision-making, and interactions with others.
The test typically includes around 200 questions and takes 30 - 40 minutes to complete. It's designed to identify consistency across your responses, so contradictory answers may raise concerns. Strong self-awareness is essential, as the qualities measured here, such as teamwork, motivation, and emotional stability, will also be observed throughout group exercises, command tasks, and interviews during the entire AOSB selection process.
Personality tests are more carefully designed than many candidates expect, analysing behavioural patterns and suitability for leadership across your full response profile.
Understanding how personality profiling works, and which traits are valued in an Army officer, is key to approaching this section with confidence. The personality dimensions assessed are likely to include emotional stability, conscientiousness, leadership presence, adaptability, team orientation, and integrity, qualities that reflect the core traits expected of a British Army officer.
Consistency across your responses matters as the test is designed to identify patterns rather than isolated answers.
Take a look at an AOSB personality test sample question:
Please indicate to which extent you agree or disagree with the following statement:
You may be thinking, “There are no right or wrong answers in a personality test.” While this is technically true, some response patterns are more aligned with the qualities expected of an Army officer. The Army is looking for individuals who can remain calm under pressure, demonstrate sound judgement, and work effectively within a team.
Remember that traits such as leadership, resilience, and teamwork will not only be assessed in this written test, but also observed throughout the AOSB process.
⭐️ Golden Tip: Be honest, consistent, and purposeful in your responses. Understanding how personality assessments are structured, and which traits are valued in an Army officer, can help you present a balanced and credible profile. Our PrepPack includes in-depth personality guides and targeted practice exercises to help you approach this section with clarity and confidence.
The AOSB Main Board Memory & Attention Test (MAT) assesses your ability to absorb, retain, and accurately apply information under time pressure. Taken as part of the Main Board (not the Briefing), it evaluates how effectively you can follow instructions and procedures, a vital skill for an Army officer where precision and attention to detail are critical.
During the test, you are shown a sequence of matrices (grids) or letters that must be memorised before answering follow-up questions. As the assessment progresses, the number and complexity of instructions increase, requiring sustained concentration and mental flexibility.
The test typically lasts around 20 minutes and your performance is measured across three key areas:
Success in the MAT depends on balancing speed with precision. Working too quickly can lead to careless errors, while over-checking instructions can cost valuable time. Developing a structured approach to memorisation and maintaining focus as the difficulty increases is essential.
Take a look at an AOSB MAT sample question:
How many letters are shown between P and R?
Choose your answer before looking at the explanation below.
The correct answer is 3.
The letters shown are P, B, L, F, R, C.
B, L, F are shown between P - R: Three letters in total.
⭐️ Golden Tip: Practise memorising information in stages and apply clear mental strategies to retain instructions under pressure. Our PrepPack includes realistic MAT-style memory tests that replicate the format and progression of the real assessment, helping you strengthen concentration, improve recall, and build confidence before the Main Board.
While our PrepPack covers the cognitive reasoning, memory, and personality sections, the AOSB also includes other critical components such as the planning exercise, command and individual tasks, fitness assessments, group exercises, and interviews.
Read more about these other aspects of the AOSB:
The AOSB Current Affairs Test takes place as part of the Main Board psychometric assessment and requires you to answer multiple-choice questions on recent national and international events, with a particular focus on issues relevant to the UK and the Armed Forces.
Success depends on both your awareness of current events and your ability to recall key details quickly under timed conditions.
Staying genuinely informed, rather than cramming headlines, will help you answer confidently and demonstrate the kind of world awareness expected of a future Army officer.
The AOSB General Knowledge Test is part of the Main Board psychometric assessment and covers a broad range of academic and cultural topics, assessing whether you have the foundational awareness expected of a future officer.
Success depends on the breadth of your knowledge and your ability to apply it quickly under timed conditions.
Candidates who read regularly and engage with the world around them tend to perform well in this test without needing to cram specific facts.
The AOSB Military Knowledge Test is part of the Main Board psychometric assessment and evaluates your understanding of the British Army, including its structure, values, key capabilities, and recent operations.
Success depends on the depth of your research and your genuine commitment to understanding the career you're applying for.
Assessors are looking for candidates who have made a genuine effort to understand Army life, not just those who have memorised facts. Demonstrating real interest and commitment will set you apart.
The AOSB Writing Test takes place on the first day of the Main Board and requires you to write a short essay on current affairs.
Success in this test depends on both your knowledge and your ability to communicate ideas clearly.
Writing concisely and clearly, using simple sentences to convey your ideas, will help you demonstrate analytical thinking and strong communication skills.
The AOSB Lecturette takes place during the Main Board and requires you to deliver a short five-minute presentation to your fellow candidates and assessors on a topic of your choice.
Success depends on your ability to communicate clearly, confidently, and engagingly, skills that are fundamental to effective leadership in the British Army.
Assessors are evaluating your presence, preparation, and ability to engage others under pressure. A confident, well-structured delivery on a topic you care about will leave a far stronger impression than a hesitant presentation on a topic chosen for effect.
The AOSB Planning Exercise (PlanEx) assesses your problem-solving and decision-making skills through scenario-based tasks.
This exercise combines individual written work with group discussion and requires candidates to analyse complex situations, consider multiple options, and produce a clear, actionable plan. Preparation should focus on breaking down problems into manageable components (aims, factors, options, and overall plan) and practising explaining your reasoning clearly.
Familiarity with scenario materials, such as maps or diagrams, and the ability to justify your plan to a group are key to performing well. Time management is also essential, as you must complete both the solo and group elements efficiently.
The PlanEx is widely considered one of the most challenging AOSB assessments given the number of components involved.
The AOSB Command and Individual Tasks evaluate leadership, teamwork, and adaptability through practical outdoor exercises. Tasks typically include obstacle courses and group problem-solving challenges, during which candidates take turns leading a group while demonstrating effective decision-making under pressure.
Preparing for these exercises involves developing strong communication skills, practising teamwork, and learning how to remain calm and focused in dynamic situations. Observing how others lead can also help you understand different approaches, while reflecting on your own leadership style will improve performance during the assessment.
The AOSB Fitness Tests measure your physical readiness and include the Multi-Stage Fitness Test (MSFT), Medicine Ball Throw, and Mid-Thigh Pull.
Candidates are expected to meet minimum standards, but preparing to exceed these benchmarks will give you a significant advantage.
To succeed as an officer, you'll need to meet the following minimum levels:
Effective preparation involves improving aerobic fitness for the MSFT, developing explosive strength for the Medicine Ball Throw and Mid-Thigh Pull, and maintaining overall endurance, strength, and flexibility. Tracking your progress and practising under test conditions will help ensure you are physically ready for the Main Board.
The AOSB Group Exercises and Interviews assess your interpersonal skills, communication, and teamwork.
To prepare, focus on practising active listening, expressing your thoughts confidently and concisely, and reflecting on your past experiences to provide clear examples of your skills, values, and leadership potential.
All of these elements are designed to assess your leadership, teamwork, problem-solving, and adaptability in practical and physical scenarios.
The AOSB covers a lot of ground, but with the right preparation, every section is manageable. Our AOSB PrepPack gives you expert-created practice tests, targeted drills, and study guides for the psychometric, memory, and personality sections, so you can build the confidence and skills needed to succeed at the Army Officer Selection Board.
The Army Officer Selection Board is a demanding process designed to identify candidates with the genuine potential to lead in the British Army. Pass rates reflect that - the AOSB is not something candidates can simply walk into unprepared.
The Army Officer Selection Board pass rate varies across its two stages.
Based on Ministry of Defence data, the average AOSB Briefing pass rate (the proportion of candidates who progress to the Main Board) historically sits at between 37–56%. Briefing outcomes are categorised as follows:
The AOSB Main Board pass rate sits at approximately 57%.
Overall, only around 32% of candidates who attend the AOSB Briefing ultimately pass the Main Board.
Thorough AOSB preparation is therefore essential, not just for passing, but for performing at a level that opens the best career pathways within the British Army.
Passing the AOSB requires more than just intelligence or fitness. Success depends on preparation, self-awareness, leadership potential, and the ability to perform consistently under pressure.
Here are key strategies to help you maximise your performance:
Ready to start preparing? Our AOSB PrepPack gives you realistic practice for the psychometric tests, Memory & Attention Test, and personality assessment, with expert guidance to help you build the speed, confidence, and mental resilience needed to perform at your best on assessment day.
Consistent, focused AOSB preparation is what separates confident candidates from those who struggle on the day. Improve your speed, accuracy, and confidence with realistic timed practice tests, and give yourself the best chance of passing the Army Officer Selection Board.
The AOSB selection process includes mental and physical assessments used to evaluate a variety of traits deemed necessary for officers.
These traits include your intelligence and fitness (stamina, agility, upper body strength, etc.), as well as your problem-solving, leadership, and teamwork skills.
The selection process takes place at AOSB Westbury and is divided into two stages, the Briefing and the Main Board.
AOSB Briefing (2 days)
The Briefing is your initial assessment and introduction to the AOSB process. During this stage, you will be placed in syndicates (teams) and evaluated across several activities designed to assess your potential.
Activities typically include:
At the end of the AOSB Briefing stage, your performance is reviewed and you are assigned a category:
Here some top tips for passing the AOSB Briefing:
Your Briefing result does not determine your final selection outcome, but it does determine whether you progress to the next stage.
AOSB Main Board (3 - 4 days)
Candidates who pass Briefing are invited to attend the Main Board. This is a residential assessment and significantly more demanding, both mentally and physically.
Activities may include:
You are assessed continuously throughout the AOSB Main Board, including informal settings such as group interaction.
Candidates are permitted two attempts at the Main Board, with a minimum of eight months between attempts.
You will only have one chance to complete the AOSB Briefing and two chances to complete the AOSB Main Board.
The AOSB Briefing pass rate (the proportion of candidates who progress to the Main Board) historically sits at between 37 - 56%, depending on how progression is measured. The AOSB Main Board pass rate sits at approximately 57%. Overall, only around 32% of candidates who attend the AOSB Briefing ultimately pass the Main Board, making thorough preparation essential.
Ensure you have the following when you head for your AOSB:
It's a good idea to bring spares.
Bring both a plain civilian suit and tie and PT clothes, including trainers, so you can present yourself well and partake in the physical activities comfortably.
Yes, Commonwealth citizens can apply to join the British Army as officers, but eligibility and application rules can change. Always check the official British Army recruitment website for the most up-to-date guidance.
The AOSB psychometric tests are designed to be challenging. Candidates must complete verbal, numerical, and abstract reasoning questions under strict time limits, often with less than 20 seconds per question. The difficulty comes not only from the questions themselves, but from the speed and accuracy required. Proper preparation and timed practice significantly improve performance.
The AOSB process is divided into two stages:
Together, the full process typically spans 5 - 6 days across two separate visits.
Preparation should cover three main areas:
Practising realistic psychometric tests under timed conditions, staying up to date with current affairs, and exceeding the minimum fitness standards will significantly improve your chances of success.
The Board assesses:
They are not looking for perfection, but for clear potential to succeed at Sandhurst.
Successful candidates receive an offer to begin officer training at the Royal Military Academy Sandhurst, where they will complete the Commissioning Course.
Yes, the AOSB is widely considered one of the most demanding officer selection processes in the world. The difficulty comes not just from individual assessments but from the sustained nature of the evaluation across multiple days. Candidates are assessed continuously, including in informal settings, on their cognitive ability, leadership potential, personality, physical fitness, and resilience. Preparation across all of these areas significantly improves your chances of success.
Both stages of the AOSB, the AOSB Briefing and the AOSB Main Board, take place at AOSB Westbury, located at Leighton House in Westbury, Wiltshire. Candidates are residential during both stages, with accommodation provided on site.
Following the AOSB Main Board, candidates receive one of the following outcomes:
If you do not pass the Main Board on your first attempt, your recruiter will provide feedback and discuss your options for reapplying.
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Kemi, Army Aptitude Tests Expert at JobTestPrep
Hi, I’m Kemi! I hold a B.Sc. in Psychology and an MSc in Organisational Psychology, and I have extensive experience in education and test development. If you have a question about our PrepPack, contact me at:
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