Treasury Minister Alex Allinson says he doesn't know how much benefit there is to letting wealthy people cap their income tax - but it could amount to £114 million over five years.
He faced a question from Ramsey MHK Lawrie Hooper about the caps, which means the ultra-rich can set a limit on their tax payments.
Dr Allinson said in 2023, 58 people elected to cap their tax - and were thought to have secured 1,100 jobs on the Island and brought £22.8 million to the Isle of Man.
He says that figure doesn't include how much rich people contribute to VAT by spending money on the Island.