A new law has come into force entitling workers to claim back-pay from former bosses.
The law means that employees who were paid less than the minimum wage in a previous job can now force former employers to pay up.
The new law could hit legal expenses insurers if employers find themselves fighting an increasing number of employee claims.
An ABI spokesman said: "This is an issue which we will examine further because it could affect insurers.
"Employers might be faced with claims for back-pay. The insurers could then be faced with hits on legal expenses policies. But it is too early to quantify the impact yet."
The Trades Union Congress (TUC) said the new law would help underpaid employees claw back what they are owed.
TUC general secretary Brendan Barber said: "The government has already recovered £13m for workers cheated out of the minimum wage. This law will help them keep up the pressure and ensure that there is no hiding place for bad bosses."
Mike Hibbs, head of employment at Birmingham law firm Shakespeares, said: "A large number of businesses will be affected by the rise in the minimum wage from 1 October this year. It's even more important than ever before that employers make sure they're paying their employees the correct wages as staff will now have the right to go back to previous employers and check their pay was calculated correctly.
"There's also the possibility that ex-employees might be more likely to go back and check they were being paid correctly once they've left a job, whereas they may not have felt able to do so while they were still in employment. The lesson is clearly to make sure you're getting it right now before problems crop up."
