"Do I need to contact my employer so they can correct my 2024 W-2 or do I only need to contact Health Equity?"
Only HealthEquity.
"How do I calculate earnings on $2,718.33? I have $3,600 cash + $50k investments in the HSA (Health Equity)."
HealthEquity should do the calculation based on the amount of excess contribution that you request to be returned and the timing of the contribution and distribution. While the attributable interest is required to accompany the distribution of the excess, it is not part of the excess contribution itself. With the value of the investments varying daily, the calculation can only be properly done using the investment values on the date that the return of excess contribution is processed, which means that the calculation needs to be done by HealthEquity.
" Will Health Equity issue some type of tax form for the excess contribution removal this year or next year? "
HealthEquity will report the distribution on a code-2 2025 Form 1099-SA. Attributable gains shown in box 2 will be taxable on your 2025 tax return.
As NCperson, said, you were an eligible individual for 10 months of 2024 because your Medicare Part A coverage did not start until 11/1/2024.
