underpay
Expensive sports shoes are being made by underpaid workers in unhealthy factories.
Childcare staff are still underpaid and undervalued.
These workers are grossly underpaid by today's standards.

underpaid | American Dictionary

underpaid
adjective
us/ˌʌn·dərˈpeɪd/
paid too little money for the work you do

underpaid | Business English

underpaid
adjective
uk /ˌʌndəˈpeɪd/us
not paid enough money for the work that you do:
He believed that the top executives were woefully underpaid.
The underpaid employees hounded their boss for a raise.
if a job is underpaid, the people who do it do not earn enough money:
Service in the catering industry has long been underpaid.
Looking after children is one of the most undervalued and underpaid jobs there is.
FINANCE, TAX
an underpaid amount of money is less than it should be:
For underpaid tax the rate will be 2.5% over bank base rate.

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