Don't bother your employer. They probably won't get to it in time.
If you were under HDHP coverage on December 1, 2023, then you can make the maximum HSA contribution for 2023 ($3,850 for self-only coverage and $7,750 for family coverage, plus $1,000 if you are 55+).
NOTE: this requires you to stay under HDHP coverage for all of 2024.
Yes, you can do this if you send the contribution directly to the HSA custodian by Monday, April 15th. Call them to make sure this happens.
***NOTE*** You MUST tell the HSA custodian that the contribution is for 2023!
You will enter this in the HSA interview (Deductions & Credits->Medical->1099-SA,HSA,MSA) on the screen "Let's enter [name]'s HSA contributions". Enter it on the second line as a "personal" contribution.
It will appear as a deduction on line 13 on Schedule 1 (1040).
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