This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Holding and Movement Alcohol Strategy - Unannounced Visits

Procedures and good practice: How many officers should attend an unannounced visit?

In most cases no more than two officers should attend. However, if there are compelling operational concerns, additional officers could attend. If a visit does require more than two officers, then the reason for this must be documented. This record should be retained with the case papers, as it could be scrutinised by the Senior Officer (SO) at a later date.