Every way to revise for the national investigators' exam
Candidates ask what to buy before their sitting. This page lists every revision option on the market, with current prices, so you can decide for yourself.
Start with the manual — whatever else you buy
The exam is marked against the current edition of Blackstone's Police Investigators' Manual, the College of Policing's designated reference text. No third-party product is an authorised substitute for it. The 2026 edition is a two-volume Manual and Workbook set, around £90 from legal bookshops.
Source: Wildy & Sons, retailer listing, price as listed August 2026.
The comparison
| Provider | What you get | Price | Access |
|---|---|---|---|
| Blackstone's Police Investigators' Manual & Workbook 2026 (Oxford University Press) | The designated reference text, two paperback volumes | Around £90 | Yours to keep |
| Police Law Prep (NIE workspace) | Revision app: 518 revision cards, 774 mixed-length multiple-choice practice questions, mock exams with the published weighting, readiness estimate | £15/month | Cancel anytime, no minimum term |
| Police Inspire | Online question bank, 1,100+ questions, iOS/Android app | £19.99 for one month, £47 for 3 months, £65 for 6 months, £71 for 12 months | Length of subscription |
| Police Pass | Four revision textbooks £69.99; multiple-choice question package £105; 4-day virtual crammer course £150; blended e-learning (40 hrs video + question bank) £235 | £69.99–£235 | Digital products are a 6-month licence that expires automatically; books are yours |
| Police Revision | E-learning package: 50+ hrs video, practice questions, 8 mock exams, 2-day online crammer | £129 (mock exams only or crammer only, £49 each) | 6 months |
| Checkmate Training / Paul Connor | Live crammer courses, revision books and audio bundles | Prices on their site | Varies |
| Julianna Mitchell Training | Audio crammer course, MP3s on USB, updated for 2026 | £80 | Yours to keep |
Prices and terms from each provider's own public pages, checked 29 August 2026. Check the provider's site before buying — prices and licence terms change.
Check the term against your sitting date
Several digital products use a fixed term. Police Pass's question package and e-learning are sold as 6-month licences that begin at purchase and expire automatically. Police Revision's package runs for 6 months. Police Inspire lists one-month, 3-month, 6-month and 12-month NIE options.
If you buy months before your sitting, or might resit, check what happens to your access when a fixed-term licence ends, and how much a rolling subscription will have cost you by then. A pass is valid for three years less a day, and resit timing is set by your force.
For one month of NIE access, Police Law Prep costs £15 and Police Inspire lists £19.99. Police Law Prep also includes NPPF Sergeants and NPPF Inspectors. Prices checked 29 August 2026.
Free ways to prepare
The College of Policing's own NIE candidate handbook is the authoritative source on format, pass mark and syllabus, and it's free. Some providers offer free samples too — Police Pass offers a free study pack, and Police Inspire and others publish free sample questions.
Police Law Prep also has a free NIE workspace: four full topics, no sign-up, at /free.
See also the other two guides on this site: how to pass the NIE and NIE exam dates 2026.
How to choose
A few neutral questions worth asking of anything on this page:
- Does it test you or tell you — recall practice (questions, mocks) versus reading or watching.
- Does the question mix follow the real paper's weighting — roughly 31/23/13/13 out of 80 across the four syllabus areas.
- Does the access window cover your sitting, and a possible resit.
- Is there a refund policy.
No product on this page wins all four by definition — the right mix depends on how you learn. Many candidates combine the manual with one practice tool.
Frequently asked
How much does NIE revision cost?
Costs vary by format. The Blackstone's Police Investigators' Manual and Workbook set is around £90. Digital question banks and courses run from £15 a month up to £235 for the largest e-learning packages. Audio crammer courses are around £80.
Do I need to buy anything beyond the manual?
No. The exam is marked against Blackstone's Police Investigators' Manual and nothing else is required. Practice products exist because rereading the manual builds familiarity rather than recall — whether you need one depends on how you study.
How long do NIE revision products last?
It depends on the provider. The manual is yours to keep. Police Law Prep is a rolling monthly subscription, £15 a month, with no minimum term. Police Pass's question package and e-learning are sold as 6-month licences. Police Revision's package runs for 6 months. Police Inspire lists one-month, 3-month, 6-month and 12-month NIE options. Julianna Mitchell's audio course is yours to keep.
Is Police Law Prep affiliated with the providers on this page?
No. Police Law Prep is independent, and not affiliated with the College of Policing, any publisher, or any of the other providers listed here. The prices and terms on this page come from each provider's own public pages, checked in August 2026.
One of your options, plainly stated
The Police Law Prep NIE workspace has 518 revision cards and 774 mixed-length multiple-choice practice questions, plus mock exams and a readiness estimate. The £15 monthly subscription unlocks NIE, NPPF Sergeants and NPPF Inspectors.