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HMRC internal manual

Employment Status Manual

Procedural aspects of status cases: telephone enquiries

Staff can receive telephone enquiries about status and offer advice over the telephone. In these cases, it should be made clear that this view is based on the information provided over the telephone and is not binding. If callers want a considered opinion on status on which they can rely, then they should write setting out the facts, terms and conditions surrounding the engagement, including any written agreement, and giving their own opinion of the status or alternatively they should be advised to use the Employment Status Indicator (ESI).

You should ensure that full records of your enquiries and opinion are kept. And, in the case of telephone calls, keep a full note including a record that it was made clear that advice given over the telephone is not binding.