The UK Government has launched an advertising campaign in a bid to raise lowest paid workers' knowledge of their rights ahead of the National Living Wage being hiked on 1 April.
The drive coincides with a poll of more than 1,400 workers, who earn less than £15,000 ($18,601) per year, which found 69% of respondents did not know they should be paid for travel time between appointments.
The survey also revealed that 57% of low paid workers did not know that having money deducted from their wages to cover the costs of their uniform is unlawful if it takes their earnings under the National Living Wage, which will rise by 30p to £7.50 per hour for those aged 25 and over.
"We are determined to make sure everybody in work receives a fair wage and while most employers get it right, there are still a small number who fail to play by the rules," said Business Minister Margot James.
"This campaign will raise awareness among the lowest paid people in society about what they must legally receive. Anyone who thinks they may be paid less than the legal minimum should contact [mediation service] Acas as soon as possible."
But Unison, the UK's second largest trade union, urged the Gvernment to do more to tackle minimum wage cheats instead of spending money on "expensive PR campaigns".
"The Government should be forcing cheating employers to make it clear to employees how their pay is calculated," said Dave Prentis, the general secretary of Unison.
"It's too easy for unscrupulous bosses to mask wage theft through complicated and opaque pay slips.
"It's also not right to put the onus on employees. Many will be nervous about querying their pay for fear of having their hours reduced or worse still getting the sack. Ministers must stop letting bad bosses off the hook."
Stewart Gee, head of guidance at Acas, said: "We welcome this new Government awareness campaign as it is important for employers to stay within the law and for workers to be fully aware of the pay that they are legally entitled to.
"Acas has free and impartial advice for both employers and employees on the correct national minimum and living wage rates and advice for workers on what they can do if they feel that they are not being paid correctly."