A random inspection of doorstaff in Bath, Swindon and Reading has shown that 95% are working with legally with Security Industry Authority (SIA) licences.
SIA officials visited 85 sites and made checks on 215 doorstaff on 3 and 4 March.
11 were given warnings on for failing to display their licence and failing to notify the SIA of a change of address.
"The results of this random compliance testing operation have provided us with much information and there is a lot of follow up work required," said Dave Humphries, director of compliance and enforcement.
"It is important to remind approved contractors that they must adhere to the terms and conditions of the Approved Contractor Scheme. Misuse of Licence Dispensation Notice can result in having this restricted or withdrawn.
"I must also remind those working in the designated security roles that neither working without an SIA licence nor breaching the licence conditions will be tolerated.
"Security staff can improve the feeling of safety in our towns and so we need operatives and those deploying them to be professional and to be operating legally."