About
About HSAProrate
A free calculator for exactly how much you can contribute to your HSA when you were not HDHP-eligible all year.
It applies the rules in IRS Publication 969 / Form 8889: monthly proration of the annual limit and the age-55 catch-up, the last-month rule, and the 13-month testing-period clawback. One person at a time; the limit is combined across you and your employer; couples share the family limit. Runs in your browser — nothing is sent anywhere. Educational estimate, not tax advice.