underpays

verb
  1. 1

    To pay (someone) less than the value of their work; to pay (someone) insufficiently.

  2. 2

    To pay less than is due for (something).

    โ€œThe underpaid letter was returned to the sender.โ€

Antonyms

Source: https://en.wiktionary.org/wiki/underpay, https://en.wiktionary.org/wiki/underpays