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HMRC internal manual

Employment Status Manual

Procedural aspects of status cases: liabilities pending an agreement

In those cases where you think PAYE and Class 1 NICs may be appropriate, tell the engager that if your opinion is confirmed they will be liable for the NICs and tax due on payments made whilst the issue is being considered (as well as for any relevant earlier period). Engagers should therefore be advised that it is in their own interest to operate PAYE and NICs in the meantime or make whatever arrangements considered necessary with the worker in view of the potential liability.