Employers are missing out on talented workers because of negative attitudes towards people who have a tattoo, says a new report.
The conciliation service Acas said a third of young people have a tattoo, but some firms, and individual managers, were worried about the image it would give to potential customers or clients.
Acas pointed out that dress codes in the workplace must not be discriminatory, suggesting that employees should be consulted.
Stephen Williams of Acas, said: "Businesses are perfectly within their right to have rules around appearance at work but these rules should be based on the law where appropriate, and the needs of the business, not managers' personal preferences.
"We know that employers with a diverse workforce can reap many business benefits as they can tap into the knowledge and skills of staff from a wide range of backgrounds.
"Almost a third of young people now have tattoos so, whilst it remains a legitimate business decision, a dress code that restricts people with tattoos might mean companies are missing out on talented workers.
"We have updated our dress code guidance today, which also includes advice for employers to help ensure they don't fall on the wrong side of the law with their dress codes."