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No. You must verify with HMRC before the first payment, but no verification is needed if you last included that subcontractor on a monthly return in the current tax year or in either of the two previous tax years. So a subcontractor you use regularly does not need re-verifying, and one you have not used for three years does. HMRC gives you a single verification reference for a batch of subcontractors; where one of them cannot be verified, the same number comes back with a unique letter on the end of it.
Verification is required before the first payment to a new subcontractor. You do not have to verify again if you have included that subcontractor on a return in the current tax year or in either of the two previous tax years.
So the practical test is not "have I paid them before" but "have they appeared on one of my returns recently enough". Someone you used two years ago and are picking up again may be inside the window; someone you used four years ago is not.
Paying an unverified subcontractor at 20% when the higher rate applied leaves you exposed for the shortfall, not them. The deduction is your obligation, and HMRC will look to the contractor for what should have been deducted. From 6 April 2026 the anti-fraud package sharpened the consequences of getting CIS obligations wrong, which makes the routine bits of the process worth doing properly rather than by memory.
The workable habit is to verify anyone new, keep the reference against their record, and check the date they last appeared on a return before paying anyone you have not used for a while.
This question is part of CIS returns and verification, which covers the whole area.
Send us three months of payment and deduction statements. We will tell you what is wrong, what it is costing, and whether gross payment status would fix it.