Ten Welsh firms have been xo168 exposed by the UK government for not paying workers the minimum wage.
The businesses failed to pay a total of £78,000 to 171 workers from 2012 to 2018.
After the investigations by HM Revenue and Customs (HMRC), the firms paid what was owed, plus £100,000 in fines.
The UK government accepted not all minimum wage underpayments were intentional, adding it was employers' responsibility to abide by the law.
It said the businesses breaking the rules underpaid workers by:
Not paying staff for all time worked
Paying incorrect apprenticeship rates
Failing to pay new minimum wage rates
Across the UK, a total of 191 companies investigated failed to pay £2.1m to more than 34,000 workers.
Business Minister Paul Scully said: "There is never an excuse to short-change workers and paying the minimum wage isn't optional."
Bosses who pay less than minimum wage must pay back workers at current minimum wage rates and face fines of up to 200% of what they owed staff - capped at £20,000 per worker.
Since 2015, the government has ordered employers to repay more than £100m to one million workers.
The government said it was committed to protecting workers' rights and was making the list public to remind businesses the government would take action against those not paying minimum wage.