MI5 asks you to keep your application to yourself, and it can take six to nine months

Prep sites consistently report a verbal reasoning test early in MI5 selection, alongside a judgement test. The verbal half of our reasoning test trains the same discipline of judging a statement strictly against a passage, and the CCAT practice test adds quick general problem solving if your role is analytical.

MI5 does not describe its online tests on the pages we found, and says the process varies by role, so we cannot tell you which tests your role uses. Our tests do not rehearse judgement scenarios, written exercises, interviews or vetting, and vetting is the longest part of the process.

MI5 advises applicants not to mention their application on social media and not to discuss it with anyone else at this stage. It also offers bespoke advice on what to tell family and friends as the process goes on. One careers guide says applicants may tell a partner or a single close family member; MI5's own guidance is the authority on that, so follow what your recruitment contact says.

That rule has a practical side effect. Most graduates prepare for assessment centres by swapping notes with friends who applied to the same scheme. You cannot do that here. Prepare alone, with general material, and do not join forums or group chats about your MI5 application.

MI5 says you may submit one application at a time and should check the eligibility criteria before you begin. It does not generally accept CVs unless a role requires one. Because applications run for months, choosing which role to apply for is a real decision: a role you are only half interested in can occupy the slot for most of a year.

Read the role page carefully and pick the one where your evidence is strongest. If the role is analytical, practise reading text and data precisely. If it is technical, the role page usually says so.

Prep sites describe the early online stage as a verbal reasoning test and a situational judgement test, and one names Cubiks as the supplier. MI5 itself does not name a supplier on the pages we found, so treat that as unconfirmed. The judgement test is reported to ask for the most appropriate response to hypothetical workplace scenarios.

For the verbal test, the habit to build is resisting what you already know. Intelligence work depends on separating what a report says from what you assume. Our verbal reasoning questions show the method. For the judgement scenarios, the answer that protects information, respects colleagues and reports concerns through the right channel is usually the strongest.

MI5 explains that its process can take six to nine months because vetting is built in. Vetting involves detailed questionnaires, a discussion with a vetting officer and agreeing references who will be interviewed. Roles that need Developed Vetting, the top level of clearance, add extensive background checks and a security interview.

The questionnaires reward honesty and completeness. Gather addresses, employment dates and contact details for referees early, and be open about anything you are unsure whether to mention. Keep other job applications moving while you wait; a long gap is normal and is not a sign of failure.

• List every address you have lived at, with dates, before the forms arrive.
• Warn your referees that they may be interviewed, without telling them more than MI5 allows.
• Keep a private note of what you declared, so later answers stay consistent.

Prep sites describe the intelligence officer route as including an assessment centre with a written exercise, followed by telephone and in-person interviews, and another guide mentions role plays and a planning exercise. These accounts are secondhand and the format may have changed, so we only offer general preparation.

Written exercises in this setting usually reward short, clear reporting: what is known, what is not, and what you recommend doing next. Practise writing a one-page summary of a news story that separates confirmed facts from claims. Our assessment centre guide covers the common exercise types.

These come from anonymous reviews, university careers pages and prep guides. They often disagree, and MI5 has not confirmed them. Read them as leads, not rules.

• Prep sites report that the early online stage includes a verbal reasoning test and a situational judgement test, and one names Cubiks as the supplier.
• A prep guide lists online pre-screening tests, a competency questionnaire, a verbal reasoning test, an assessment centre written exercise and then telephone and initial interviews for the intelligence officer scheme.
• Another guide describes an assessment centre with situational role plays, a planning exercise and an interview.
• A careers guide says applicants may discuss their application with a partner or one close family member only.