News · End-Hirers & Recruitment Agencies · OPRaaS Platform
Labour supplier due diligence rests on a plain discipline: before you rely on a supplier, you verify that they are who they say they are. HMRC has just restated that same habit for its own contacts, refreshing the guidance that helps businesses check whether a letter, call, email or text claiming to be from HMRC is genuine.
The guidance, Check genuine HMRC contact that uses more than one communication method, was updated on GOV.UK on 5 June 2026. It exists because criminals can impersonate HMRC convincingly, and because HMRC itself may use several channels in sequence, such as a letter followed by an email, call or text. Its instruction is simple: do not assume a contact is genuine because it looks official; check it against a known, independent reference.
That instruction travels well. The same reflex, verify before you act rather than take an assurance on trust, is exactly what end-hirers and recruitment agencies are expected to apply to the suppliers, umbrellas, payroll intermediaries and payers in their labour supply chain.
Why HMRC keeps restating a verify-first habit
The genuine-contact guidance is, on its face, about scams. Underneath, it teaches a method. HMRC lists the contacts it is currently making and the channels each one may use, so a recipient can match what has landed in front of them against a published reference rather than judge it by tone, logo, formatting or confidence.
The logic is worth naming. A message that looks official is not evidence that it is official. Assurance comes from an independent check, not from the polish of the thing being checked.
That is the same distinction that separates a supplier who feels reputable from a supplier who has actually been verified. Closing that gap is what labour supplier due diligence is designed to do.
The same test, applied to a labour supplier
Move the method from a suspicious HMRC text message to a new payroll intermediary, and labour supplier due diligence is what you get. A recruitment agency or end-hirer engaging an umbrella company, sub-agency, CIS payer or other labour provider faces the same question the HMRC guidance poses: is this party genuine, and how do I know independently of what they have told me?
HMRC has its own published answer for labour supply chains. In 10 things about due diligence: supply chain assurance, it asks businesses to make sure their labour supplier is legitimate, understand where workers are coming from, check how they are being paid, verify the supplier’s VAT registration through the GOV.UK VAT number checker, test whether the arrangement is commercially sustainable, and confirm workers are paid the correct rate.
Each of those is a point to evidence, not a point to take on trust. Whether the contact is a text message or a supplier onboarding pack, the safe move is the same: check it independently.
What taking a supplier on trust can cost
The consequences of a bad supplier do not always stay with the supplier. Where a labour provider is not paying the tax it should, HMRC can look up the chain to the businesses that engaged it. An end-hirer or recruitment agency that assumed an umbrella was compliant, rather than verifying it, can find the exposure landing on its own desk.
The risk is rarely loud at the point of engagement. A non-compliant payer can look ordinary: an invoice, a rate, a payslip, a portal login, a reassuring conversation. The gap only appears when someone asks for the evidence and there is none, because the relationship was built on confidence rather than verification.
Labour supplier due diligence is the work that closes that gap before it opens.
Where the OPRaaS LSCA course teaches labour supplier due diligence
This is the territory the OPRaaS Labour Supply Chain Assurance Self-Certification Course works through in Module 4, on supply chain risk assessment, due diligence and documentation.
The module organises labour supplier due diligence around HMRC’s Check, Act and Review principles: the verify-don’t-assume habit turned into a repeatable control cycle.
Check
Check is where you identify and understand the risk in a supplier before you rely on them. The module asks you to confirm legal obligations such as PAYE, VAT, CIS and right to work, assess the supplier’s financial stability against insolvency risk, and obtain evidence that tax deductions are actually remitted to HMRC, not merely shown on a payslip. Verification, not reassurance.
Act
Act is the due diligence itself, documented. Where a risk surfaces, the course expects prompt action: work with the supplier to resolve it, or remove a supplier whose risk cannot be resolved. It also fixes accountability in the right place. A third party may help with the checks, but the engaging organisation remains accountable for its supplier choices.
Review
Review is what stops due diligence becoming a one-off gate. The module treats it as continuous: reassess supplier compliance and risk on a regular cadence, update the checks as the rules and the business change, and feed findings from audits or incidents back into the process. A supplier verified once is not a supplier verified for good.
A supplier you have not checked is a supplier you are taking on trust. Due diligence is simply the work of replacing that trust with evidence.
How the OPRaaS Virtual Compliance Director keeps verification live
The OPRaaS Virtual Compliance Director (OPRaaS VCD) platform embeds senior governance leadership into a recruitment agency or end-hirer without the cost of a full-time director. It treats labour supplier due diligence as a standing control rather than an onboarding formality, building audit-ready controls across right to work, IR35, CIS, GLAA, modern slavery and HMRC’s wider labour supply chain expectations.
Two examples make it concrete. Each supplier umbrella and sub-agency can be monitored against Companies House for director and ownership changes, and against credit-risk indicators such as county court judgments and financial-strength downgrades, so a supplier that was sound at onboarding does not quietly drift out of compliance unnoticed.
VAT registration, right-to-pay evidence and worker pay rates can be re-checked on a risk-based cadence, with each result written into the supplier’s evidence record. The point is not to slow supplier onboarding down. It is to make sure the decision to rely on a supplier remains defensible after the first file has been approved.
OPRaaS, On-Pay-Roll-as-a-Service, is a systemised governance and workforce management partner for organisations that rely on temporary, contractor and contingent labour, from recruitment agencies and end-hirers to umbrella companies, managed service providers and public sector buyers. It is approved on UK Government Commercial Agency frameworks including RM6310 Audit & Assurance Services Lots 2 & 4, RM6219 and RM6237 Learning & Training Services DPS.
Why labour supplier due diligence sits with the board
The board-level point is the one HMRC keeps making in plainer territory. You cannot tell a genuine contact from a convincing fake by looking at it, and you cannot tell a compliant supplier from a confident one in the same way. Both require an independent check, kept current.
For public sector buyers this is sharper still. NHS trusts, councils and multi-academy trusts rely heavily on agency and contract labour, often through layered supply chains. If a supplier is not verified properly, the risk can move upstream to the principal that relied on them.
The practical reframe is straightforward: stop asking whether a supplier seems trustworthy, and start asking what you have verified, where the evidence sits, and when you last checked it. That, in practice, is what supplier due diligence becoming a continuous control rather than a procurement gate looks like.
Compliance is your asset. Evidenced daily.
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“Own your compliance as an asset.”
Drawing on HMRC’s guidance Check genuine HMRC contact that uses more than one communication method, updated on GOV.UK on 5 June 2026; HMRC’s guidance on labour-provider due diligence; the GOV.UK VAT number checker; and the OPRaaS LSCA Self-Certification Course Module 4.
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This article is editorial commentary by OPRaaS Limited (On-Pay-Roll-as-a-Service), drawing on published HMRC guidance. It is general information, not legal, tax, employment or compliance advice. Obligations vary by organisation and engagement. Speak to a qualified professional before acting on any specific position.