How to Complete the SIA ACS Self-Assessment Workbook (2026 Update)

The SIA ACS self-assessment workbook is the PDF self-test you complete before applying for Approved Contractor Scheme approval. You work through 78 indicators across seven criteria, tick the level you genuinely meet for each one and keep notes on how you meet it. To qualify, you must meet the required achievement level on every indicator that applies to you, and the workbook then gives you a score out of 145 to put on your application form.

This guide shows how to fill in the workbook properly for 2026: what each criterion asks, the evidence a 10 to 50 officer company can use, what changed in the 2026 update and the mistakes that cost points. It sits alongside our main guide to how to get SIA ACS approval, our breakdown of whether SIA ACS is worth it for a small security company and our SIA ACS accreditation support hub.

What is the SIA ACS self-assessment workbook and who completes it?

It is an interactive PDF that the Security Industry Authority publishes on GOV.UK. Your company completes it, and the SIA says that can be senior management, a cross-section of managers or staff, or whoever is responsible for quality or standards. The SIA recommends involving as many people as possible so the result is a true reflection of the business.

The workbook is not a form you send in on its own. The process runs in this order:

1. Download and complete the workbook. For each indicator you tick the levels you meet and add notes. You can save and return to it as often as you like.
2. Complete the ACS application form. It includes the performance score from your workbook. You submit it through your SIA online business account.
3. Receive the SIA’s letter of acceptance. You then appoint an assessing body and have six months to complete a successful assessment.
4. Share your workbook data with the assessor. The workbook has a submit button that prepares the data file for your assessor. They use it to plan the verification visit.
5. The assessor verifies and reports. They compare their findings with your self-assessment and send their report to the SIA and to you.

Once you are approved, the workbook comes back every year. For standard route annual assessments you review and update your previous self-assessment, allowing for any organisational changes and the comments from your last assessment, and send it to your assessor at least six weeks before the assessment.

What changed in the 2026 update to the ACS workbook?

The SIA first published the workbook page on GOV.UK on 19 January 2026 and updated it on 1 July 2026, when it added a “2026 update to the ACS self-assessment workbook” note and replaced the ACS workbook guide with a new version. The 2026 update changed two indicators and the glossary:

The update page does not set out transition dates for existing approved contractors, so check your assessing body’s advice if you are already approved. If you built your answers on an older copy, re-read these two indicators before you submit anything.

How does ACS scoring work in the workbook?

Every indicator has a required achievement level, and many also have one to three improvement levels. You tick the box for each level at which you meet all the statements, working upwards, and stop at the highest level you completely achieve. The workbook records your result per criterion and gives an overall performance score between 0 and 145.

Two points matter here. First, the workbook does not set a minimum overall score. The test for approval is that you meet the required achievement level for all 78 indicators, apart from any that genuinely do not apply to you. The score, which reflects the improvement levels you reach, goes on your application and is what buyers compare later. Second, over-claiming hurts. The assessor verifies your claim, and the SIA says you are responsible for representing your organisation accurately, so a tick you cannot evidence is a problem, not a boost.

What if an indicator does not apply to us?

You still have to record it. Tick the required achievement level box only and use the notes to explain why it does not apply. The SIA warns not to assume an indicator is not applicable just because you do not currently do something, and says the number of genuine exceptions is generally very low. A company that uses no subcontractors, for example, can mark 2.4.1 as not applicable, but the assessor will test that against your staff records and conversations.

How long does it take?

The SIA says to allow about an hour to get familiar with the workbook. The completion time depends on your size: roughly a day for a small organisation with turnover up to £1 million and as much as five days for a large or multi-site organisation with turnover over £4 million. That is the time to answer, not to gather evidence, so start collecting records first.

How do you complete the workbook criterion by criterion?

The table below uses the SIA’s own one-line description of each criterion and the evidence we would expect a 10 to 50 officer guarding or events company to be able to show. The evidence column is practical guidance based on the SIA’s workbook guide, not an official checklist.

Three details from the SIA’s guide are worth knowing before you start:

• Informal can be fine. For indicators such as your approach to business, the guide accepts that a leader who can explain it verbally may be enough, because the assessor will check with staff and customers. A plan does not have to be a formal document, but it must exist and be reviewed.
• Finance is a light touch, not a forensic one. For 4.1.1 the guide says the assessor is not expected to examine accounts in detail, but you must show that you meet your debts as they fall due. If you are VAT registrable, the guide expects evidence of registration and VAT payments made on time for at least 12 months.
• ISO 9001 helps, but it is not a substitute. The workbook says a company that meets all the requirements of ISO 9001 can expect to meet the required level for around two thirds of the indicators. You do not need ISO 9001 to be approved. See our ISO 9001 hub if you are considering both.

What do weak and strong workbook answers look like?

The notes box under each indicator is where small companies either show their evidence or give themselves away. These are illustrative examples of the difference. They are our examples, not SIA wording, and the indicators are the ones where we most often see thin answers.

The wage example reflects the workbook’s required level for 6.4.2, which asks that the national minimum and real living wage rates are adhered to or exceeded for basic take-home pay. The SIA’s guide also notes that wage calculations should not include holiday pay, transport or accommodation costs.

The insurance indicator, 4.2.4, catches companies out in a different way. The guide says the cost of business insurance should not be passed to staff through pay deductions, that hazardous activities must be disclosed to insurers, and that subcontractors must be covered under your cover where they have none of their own. For staff records, the guide also expects licences to be checked regularly against the public register, with a copy of the website screenshot kept as due diligence.

How does the assessor use your workbook on assessment day?

The assessor uses your workbook data to plan the visit, then checks your claims against evidence. The SIA says assessors take a holistic view of your business rather than ticking each indicator in isolation. In practice they will:

• review your self-assessment workbook, staff list, contracts and sector breakdown before the assessment;
• visit your head office, control room if you have one, and operational sites;
• review policies and documents and look at your online platforms and how you handle data;
• interview staff, subcontractors and customers, including past customers.

After the visit the assessor updates their version of your self-assessment report so you can see where their view differs from yours, and then sends their full report. Our guide to SIA ACS assessment preparation covers the visit itself in more detail. A workbook answer that sounds good but cannot be matched to a record, or that a supervisor contradicts, is the usual reason a claim fails.

What are the six most common workbook mistakes?

1. Copying a template or another company’s answers. The assessor asks staff and customers about your actual practice. Generic wording that does not match what officers say will not hold up.
2. Claiming a process with no records. If you say you check SIA licences monthly, there should be a dated log. If you say you review incidents, there should be reviews. The guide repeatedly refers to evidence and examples.
3. Ticking a level you only partly meet. You must meet all the statements at a level before you move up. One missing statement means the box stays empty.
4. Treating “not applicable” as a shortcut. The SIA expects very few indicators to be not applicable, and wants an explanation for each in the notes.
5. Missing the 2026 changes. Check your subcontractor arrangements and your payroll for personal service company operatives before you answer 2.4.1 and 4.2.1.
6. Leaving the notes empty and having no improvement plan. The SIA says the notes help you build an improvement plan and help the assessor plan the visit. Indicators that you meet only at the required level are where your score can grow next year.

What does an evidence tracker for the ACS workbook look like?

A simple tracker keeps your answers and your proof in one place. The entries below are illustrative. Copy the structure into a spreadsheet and add a row for each of the 78 indicators.

Add a column for any improvement level you plan to reach next. Doing this as you go makes the six-week annual deadline far less stressful.

Frequently asked questions

Can I complete the ACS workbook myself?

Yes. The SIA designed the workbook for companies to complete themselves, and its guide says using the guide is helpful but not obligatory. The SIA recommends involving managers from across the business rather than leaving it to one person. Many companies use a consultant to check evidence before the assessor does, but the assessor is the one who verifies your answers.

How long does the self-assessment take?

The SIA says about an hour to get familiar with it, roughly a day for a small organisation with turnover up to £1 million and up to five days for a large or multi-site organisation. Gathering and organising the evidence usually takes longer than answering the questions.

What score do I need to pass ACS?

The workbook does not state a minimum overall score. To be eligible you must meet the required achievement level on all 78 indicators, apart from those that genuinely do not apply. Your score out of 145 reflects the improvement levels you reach beyond that.

Can I change my workbook after submitting?

Your workbook is a file you save and control. The SIA’s process includes a step to amend it and share the updated data with your assessor, and it says that sharing the correct data is the business’s responsibility. For annual assessments you update the previous workbook and send it at least six weeks before the assessment. Ask your assessing body how they want late changes handled.

What are ACS Pacesetters?

ACS Pacesetters is an independent initiative linked to FM Contract Watch LLP, not sponsored by the SIA. It says its membership is made up of contract security guarding companies in the top 15% of the benchmarking levels set by the Approved Contractor Scheme, and that a score of 110 or more is needed. It is separate from the workbook and from SIA approval itself.

Sources: ACS self-assessment workbook; 2026 update to the ACS self-assessment workbook; SIA ACS workbook guide, July 2026; Apply for ACS approval; Understanding ACS assessments; Understanding annual ACS assessments; ACS Pacesetters. Last checked: October 2026.