Contractor Prequalification Schemes and Fees Compared

This article looks at contractor prequalification schemes from the side of the company asked to join one: who pays, what the fee depends on, which amounts are published, and what the scheme actually checks for the money. We opened each scheme's own pages, and the UK guidance and law behind them, on 21 October 2026. We did not sign up or request a quote. It is general information, not legal advice.

Two related pages cover what this one leaves out. The contractor prequalification playbook is about running prequalification inside your own organisation, and the contractor management buyer's guide is about software that a hiring client runs for itself.

The short answer

• Two bills, not one. The contractor pays for its own membership or certification, and where a scheme sells a client side, the hiring client pays for that separately. ComplyWorks is the one case where the supplier terms leave it to the client's own contract to decide which of the two pays.
• Headcount drives most contractor fees. ISNetworld bases its fee on a three-year average of everyone in the workforce and on the countries worked in. SafeContractor bases it on employee numbers and on how fast a plan's service is. Avetta bases it on the number of client connections and the risk of the work.
• Few amounts are public. On 21 October 2026 Avetta showed a $249 starting price for its Directory, which does not connect you to a client, and SafeContractor showed annual starting prices of £419 to £549 plus a joining fee. ISNetworld and ComplyWorks showed no amount on any page we opened.
• No law we read requires membership. The legal duty sits with the business that hires: take reasonable steps to check that a contractor is competent. A scheme certificate is one way to show that, not the only way, and not enough on its own to start work on a project.

Which schemes this article covers

The rule we applied to every one of the 212 vendor profiles we research: include the profile when its record describes a network or certification that a hiring client asks its contractors to join and be checked through. Four records meet it: Avetta, ComplyWorks, ISNetworld and SafeContractor, whose profile is filed under Alcumus. Software that a hiring client buys to keep its own contractor records, with no membership on the contractor's side, falls outside the rule.

The UK schemes that belong to Safety Schemes in Procurement (SSIP) are treated as one group, because SSIP makes their health and safety assessments interchangeable. We did not collect their individual prices.

Rows are in alphabetical order. Nothing here ranks the schemes or suggests which one to join, and each profile's pricing section keeps its fuller fee record.

Disclosure. The editor works at a software vendor that pays for sponsored placement on this site. That vendor's profile was tested against the rule above like the other 211. It runs no contractor network, so it does not appear in this article.

Who pays, and what the fee depends on

All rows were read on the schemes' own pages on 21 October 2026.

Notes behind each row

Avetta. The plans page ties supplier plans to the number of client connections and to the risk level of the project or trade, and says a client-connected plan is needed before working for a client. The Directory page gives the $249 yearly starting price without a tax or currency note beyond the dollar sign, and warns that features vary by region, eligibility and membership. An add-on called Vetify assigns a compliance specialist to a supplier; no price is shown for it. Older client-programme pages are still online at pages.avetta.com. The two we opened, for MasTec and for Tarmac, describe a one-time registration fee for suppliers new to Avetta, $249 on one and £124.50 on the other, then a yearly fee set by the number of client sites, the services provided and the documents that client asks for, and a promotion with lower rates for two- or three-year memberships. Neither page carries a date, so read them as history rather than as a current price list.

ComplyWorks. It is sold by Veriforce Canada. Its product page is written for hiring clients and leads to a demo request. Neither that page, the general and contractor FAQs nor the sign-up page shows a fee. The supplier terms of service on the ComplyWorks server (Veriforce LLC, version 1.2 of August 2025) say that the client's master agreement with the vendor decides whether the supplier or the client pays; when the client pays, the supplier is not asked for payment details. When the supplier pays, fees exclude taxes and are not refunded, and a fee change applies from the next renewal. The terms tie renewal to a period equal to the expiring term or one year, whichever is shorter, unless either side gives written notice of non-renewal at least 30 days before the term ends. A fee still unpaid 30 days after expiry leads to suspension, and a reactivation fee is then due on top of what is owed.

ISNetworld. The pricing panel on the contractor page explains the basis but gives no amount. Both fees follow the three-year average of the whole workforce and the countries the company works in; ISN may ask for documents to back the headcount, and reporting for more than one country can need extra subscriptions. A company with divisions can use Related Accounts: the parent's fee follows the headcount of every entity, and each subsidiary pays a fixed yearly fee. The FAQ calls the subscription all-inclusive whatever the number of tools used or clients connected, and the contractor page says new client connections cost nothing extra. Hiring clients, contractors that manage their own subcontractors (Contractor Operator) and companies that use the platform for their own training records each take a separate type of subscription.

SafeContractor. The pricing page shows four plans. They differ in how soon SafeContractor makes first contact (within 7 working days on Standard, within 1 on Premier), how soon it reviews the assessment (within 20 working days on Standard, within 2 on Express and Premier), and whether an application assistant is assigned (Assisted and Premier). The amounts are starting prices for smaller businesses; the yearly price grows with employee numbers, and a one-off joining fee is added. The FAQ says a certificate lasts 12 months, memberships renew automatically unless cancelled at least 14 days before the renewal date, and a reminder is sent 60 days before expiry. The site is run by SafeContractor Limited. The former Alcumus group site now only points visitors to SafeContractor and to ISOQAR, under a Veriforce Holdings Limited copyright line.

What each scheme checks

A fee buys a check, but not always the same kind: a desktop review of uploaded documents, a review of insurance against a client's limits, or a visit and interviews. Find out which one your client's requirement triggers before comparing prices.

ISN's disclaimer page is worth reading before relying on any of these results. It presents RAVS results as guidance, leaves each hiring client responsible for deciding whether a contractor conforms, and says a RAVS 360 assessment does not judge whether a written programme is effective. That split of responsibility matches the legal position further down.

UK: SSIP, deem to satisfy and the Common Assessment Standard

SSIP and mutual recognition

SSIP does not assess anyone itself. Its member schemes do the assessments, all against one threshold, the SSIP core criteria. According to SSIP's page on HSE's view, those criteria were first published by HSE in Appendix 4 of the approved code of practice for CDM 2007, and SSIP wrote them into its own rules, in agreement with HSE, when CDM 2015 arrived without a new code. The same page says HSE sits on the SSIP forum as a co-opted member without a vote and uses that seat to make sure each member scheme's process is audited independently every year. SSIP's home page counts more than 90,860 suppliers registered with a member scheme, a figure it dates to 12 January 2026.

Deem to satisfy is where a contractor can save money. A supplier certified by one registered member can ask another registered member to recognise that certificate instead of going through a full new assessment. The second scheme checks the certificate on the SSIP Portal and may ask for a little more. In SSIP's table that is most often insurance details; some schemes ask risk-profile questions, trade association requirements or a site audit instead.

SSIP's table of equivalences, opened on 21 October 2026, lists 25 registered member products. For 15 of them it shows a deem-to-satisfy cost saving stated by the scheme, ranging from 0% to 92%; the other 10 show "POA". Avetta's SSIP product, Avetta Assessed, shows 0% to 35%, and SafeContractor shows 0% to 20%. Certificates from certification bodies that combine SSIP with ISO 45001 only work one way: they can be used to join a registered member scheme, but a registered member's certificate cannot be used to join them.

Two practical consequences follow. A client that names one SSIP scheme may still accept another, and SSIP publishes a model letter to buyers for asking. And a recognised certificate depends on the original: SafeContractor, for example, suspends its own certificate when the underlying certificate from another SSIP scheme expires.

The Common Assessment Standard

Build UK's Common Assessment Standard (CAS) is an industry-agreed question set, with assessment standards, for prequalifying construction suppliers. It covers more than health and safety. A Recognised Assessment Body certifies a company once a year, at one of two levels, desktop or site-based, and micro-businesses are assessed proportionately. Build UK's page says the standard includes a Building Safety section for showing capability under the Building Safety Act, and that version 6 of the question set will be published on 1 November 2026. A company certified by one body can share its data with the others by filing each body's data-sharing form and emailing its original assessor to give permission.

The full list of Recognised Assessment Bodies as Build UK published it on 21 October 2026:

SSIP's FAQ draws the line between the two. Every member's core health and safety assessment is equal; products that cover CAS or PAS 91 go beyond health and safety; and a contractor that only needs a health and safety assessment does not need to upgrade. For public buyers, Build UK says central government and the wider public sector should use CAS to prequalify suppliers under the Cabinet Office's procurement policy note PPN 03/24. The note itself, published on 27 March 2024, applies to above-threshold procurements under the Public Contracts Regulations 2015, and its main text does not name CAS.

PAS 91 has been withdrawn

BSI's catalogue lists PAS 91:2013+A1:2017, the construction prequalification question set, as withdrawn on 21 April 2023, and PPN 03/24 removed the references to it for that reason. Some scheme pages still mention it: SafeContractor's pages, for instance, say its certification meets PAS 91 as well as SSIP. If a buyer asks for PAS 91, ask whether it means the CAS question set or a scheme product that still uses the old name.

Is membership required by law?

No law we read makes membership of any scheme compulsory. The duties fall on the business that hires, and they are written as reasonable steps, not as a certificate.

• Great Britain. Under section 3 of the Health and Safety at Work etc. Act 1974, every employer must run its undertaking so that, so far as is reasonably practicable, people outside its employment who may be affected are not exposed to risks to their health or safety. Under regulation 8(3) of CDM 2015, whoever appoints a designer or contractor must take reasonable steps to be satisfied that it has the skills, knowledge and experience, and for an organisation the organisational capability, for the role. HSE's page for contractors gives two examples of showing that capability: an assessment by a third-party assessor such as an SSIP member, or self-assessment against the standard health and safety questions in Build UK's CAS. SSIP's page on HSE's view goes further: the law does not require a third-party prequalification assessment, and a certificate on its own is not enough to start work, because the client should still check the supplier's skills, track record and capability for the project in hand.
• United States. OSHA's multi-employer citation policy (CPL 02-00-124) expects a controlling employer to take reasonable care, at its site, to prevent and detect violations, judged by its inspections, its system for correcting hazards and its enforcement. How much it knows about a contractor's safety history affects how closely it should inspect. The directive names no prequalification service.
• Australia. Under the Commonwealth Work Health and Safety Act 2011, section 19 makes a business ensure, so far as is reasonably practicable, the health and safety of the workers it engages or causes to be engaged, and section 46 makes duty holders who share a matter consult, cooperate and coordinate. Neither section mentions a prequalification scheme.

So a hiring client may make a scheme a condition of its contract, and many do; that condition comes from the client, not from the statute. The buyer's guide on what the law asks of the hiring business and section 1 of the playbook set out these duties in more detail. For the CDM roles themselves, see CDM regulations.

Scheme records and your own records

A scheme answers one question: is this company acceptable at the prequalification stage? It does not hold your site induction, the permit for a particular job, the incidents on your site or whether a given worker is trained for today's task. Those stay in your own records, linked to the scheme status and its expiry date. The contractor compliance record template gives one layout, the site induction software guide covers the gate, and the head-to-head pages for ISNetworld and ComplyWorks and Avetta and ComplyWorks set two documented scopes side by side.

Questions to ask before anyone pays

Ask the hiring client:

• Which schemes do you accept, and will you accept another SSIP member's certificate, or a CAS certificate from any Recognised Assessment Body?
• Which level do you need for this work: a desktop review, an insurance review or a site audit?
• Who pays the contractor's fee, and does your agreement with the scheme say so?

Ask the scheme:

• The amount for our headcount and countries, the joining or setup fee, and whether tax is included.
• The renewal date, the notice needed to cancel, and any reinstatement or reactivation fee.
• Whether connecting to another client costs more, and whether a recognised SSIP certificate or a multi-year term lowers the price.

What we could not verify (21 October 2026)

• Amounts behind sign-up. We did not register with any scheme or request a quote. ISNetworld's contractor-side and client-side amounts, Avetta's client-connected and hiring-client amounts, ComplyWorks' amounts, SafeContractor's joining fee and its employee bands, and whether SafeContractor's prices include VAT were not on the pages we opened. ISN's site search showed no results in our browser, so we cannot rule out a page it did not surface.
• Avetta's older pages. The MasTec and Tarmac programme pages carry no date. We cannot tell whether their registration fees still apply.
• ComplyWorks client documents. Search results point to supplier packages that individual hiring clients host on the ComplyWorks server, some with fees by headcount band. We did not open them: they are one client's terms, and we could not confirm their dates. We read the supplier terms of service as text extracted from a PDF, not in a browser.
• Other SSIP schemes. We did not collect the prices of CHAS, Constructionline, SMAS Worksafe, Acclaim or any other SSIP member. The deem-to-satisfy cost savings are each scheme's own figure, and SSIP's table is undated.
• HSE's own words. The statements that the law does not require a third-party assessment, and that HSE encourages clients to accept any SSIP member's certificate, come from SSIP's page on HSE's view. Neither HSE page we read contains them: the page for contractors gives the SSIP and CAS routes as examples, and the page for commercial clients mentions neither scheme.
• Public procurement. We read the main text of PPN 03/24, not its annexes, so we could not check whether the annexes are where Build UK's reading that public bodies should use CAS comes from. We did not check how the note sits alongside procurements run under the Procurement Act 2023.
• Ownership. The Veriforce names come from page footers and from Build UK's list. We did not check company filings.
• US and Australian law. We read OSHA's directive and the Commonwealth WHS Act only, not state laws, state OSHA plans or court decisions.

FAQ

Answers checked on 21 October 2026.

Is SSIP or ISN membership a legal requirement?

No law we read requires it. In Great Britain, CDM 2015 asks whoever appoints a contractor to take reasonable steps to be satisfied that it is competent, and HSE gives an SSIP assessment as one example of evidence, next to self-assessment against Build UK's question set. In the United States and Australia the duties fall on the hiring business and name no scheme. A hiring client can still make membership a condition of its contract.

Does SSIP membership satisfy CDM 2015?

It can show organisational capability at the prequalification stage: in the statement of HSE's view on SSIP's site, HSE encourages clients to accept a valid certificate from any SSIP member scheme for that stage. It does not cover the project itself. The client still has to check the contractor's skills and capability for the work in hand, and SSIP's mutual recognition covers health and safety only.

Who pays for ISNetworld or Avetta?

At ISNetworld both sides pay, for different things: the contractor pays for its own subscription, and the hiring client pays a yearly fee for each global region it uses, plus a one-time setup fee. At Avetta the supplier pays for its plan; the plans page shows no hiring-client plan and describes Avetta's pricing as customised.

Do I pay again for each new hiring client?

It depends on the scheme. ISNetworld says new client connections carry no extra fee. Avetta prices supplier plans by the number of connections. Under SSIP, a second scheme can recognise your existing certificate through deem to satisfy, which several schemes price below a full assessment.

Is PAS 91 still in use?

BSI withdrew it on 21 April 2023, and PPN 03/24 dropped the references to it. Some scheme pages still mention it, while Build UK says public bodies should prequalify construction suppliers with the Common Assessment Standard.

Sources

Read on 21 October 2026.

• ISNetworld: contractors and suppliers page with its pricing details panel, hiring clients page, FAQs, RAVS disclaimers
• Avetta: plans, Directory for suppliers, client-programme pages for MasTec and Tarmac (undated)
• SafeContractor: contractor certification plans, hiring client pricing, SSIP, what we cover, contractor FAQs, about us; Alcumus group site
• Veriforce Canada: ComplyWorks product page, general FAQs, contractor FAQs, product sign-up; ComplyWorks supplier terms of service (PDF, version 1.2, August 2025)
• SSIP: home page, deem to satisfy and table of equivalences, FAQ, view from HSE
• Build UK: Common Assessment Standard
• BSI Knowledge: PAS 91:2013+A1:2017
• Cabinet Office: PPN 03/24, Standard Selection Questionnaire (27 March 2024)
• HSE: Are you a contractor?, Are you a commercial client?
• legislation.gov.uk: Health and Safety at Work etc. Act 1974, section 3, CDM 2015, regulation 8
• OSHA: Multi-Employer Citation Policy, CPL 02-00-124
• Federal Register of Legislation: Work Health and Safety Act 2011 (compilation of 1 July 2024), sections 19 and 46