Moved from Idaho to Mississippi Mid-Year: Which State Tax Returns Do You File?
Answer
You file two part-year returns. Idaho taxes the income you received while you lived there, Mississippi taxes the income you received after the move, and each state prorates your deductions and credits to its own slice of the year. The date you changed domicile is the dividing line.
Last verified
A mid-year move splits the tax year in two, and each state taxes its own half. That is a residency question, so the machinery that governs commuters — reciprocity agreements, convenience rules, nonresident withholding — is beside the point here.
What you file
- 1Part-year return · IdahoForm 43 (part-year resident)
File a Idaho part-year return covering the months you lived in Idaho. A part-year resident of Idaho reports the income received while a Idaho resident, plus any Idaho-source income received during the rest of the year, and prorates the deductions and credits to the residency period.
- 2Part-year return · MississippiForm 80-205
File a Mississippi part-year return covering the months you lived in Mississippi. A part-year resident of Mississippi reports the income received while a Mississippi resident, plus any Mississippi-source income received during the rest of the year, and prorates the deductions and credits to the residency period.
The two states, side by side
| Idaho | Mississippi | |
|---|---|---|
| Taxes wages | Yes — flat | Yes — flat |
| Reciprocity partners | None | None |
| Convenience rule | No | No |
| Nonresident return | Form 43 | Form 80-205 |
| Part-year return | Form 43 (part-year resident) | Form 80-205 |
| Credit for other-state tax | Form 39NR | Form 80-160 |
| Nonresident safe harbour | None published | None published |
| Local income tax | No | No |
| Revenue department | Idaho State Tax Commission | Mississippi Department of Revenue |
| Last verified |
The other direction
Reversing the commute does not always reverse the answer. Living in Mississippi and working in Idaho gives:Two part-year returns.
Same two states, different situation
The withholding answer turns on how you are paid and where the work happens, not only on which two states are involved.
- W-2 commuter: Idaho → MississippiBoth states — credit offsets the double tax
- Remote worker: Idaho → MississippiHome state only
- 1099 contractor: Idaho → MississippiHome state, plus the client state if you work there
Other Idaho pairs
Questions people actually ask
I moved from Idaho to Mississippi mid-year. Do I have to file in both states?
You file two part-year returns. Idaho taxes the income you received while you lived there, Mississippi taxes the income you received after the move, and each state prorates your deductions and credits to its own slice of the year. The date you changed domicile is the dividing line.
How do I split my income between Idaho and Mississippi?
By when you received it, measured against the date your domicile actually changed. Income received while you were a Idaho resident belongs on the Idaho return and income received afterwards on the Mississippi return, with each state prorating your deductions, exemptions and credits to its own part of the year. Keep evidence of the move date — a lease, a closing statement, a licence issue date.
How current is this?
The Idaho and Mississippi rules on this page were last checked against Idaho State Tax Commission and Mississippi Department of Revenue on 2026-08-07. We re-check the full grid every December after state legislative sessions close, and re-check the convenience-of-the-employer states quarterly because that is where the rules move fastest.
Sources
Every fact above comes from the revenue department that publishes the rule. We do not cite secondary summaries, and we do not restate a figure we could not find at source.
- Idaho State Tax Commission — individual income taxaccessed 2026-08-07
- Mississippi Department of Revenue — individual income taxaccessed 2026-08-07