Moved from New Jersey to Montana Mid-Year: Which State Tax Returns Do You File?
Answer
You file two part-year returns. New Jersey taxes the income you received while you lived there, Montana 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
Part-year returns are designed so that neither state taxes the whole year. The risk is not double taxation by default; it is misassigning income received near the move date, and losing the proration on deductions and credits.
What you file
- 1Part-year return · New JerseyForm NJ-1040 (part-year resident)
File a New Jersey part-year return covering the months you lived in New Jersey. A part-year resident of New Jersey reports the income received while a New Jersey resident, plus any New Jersey-source income received during the rest of the year, and prorates the deductions and credits to the residency period.
- 2Part-year return · MontanaForm 2 with the nonresident/part-year schedule
File a Montana part-year return covering the months you lived in Montana. A part-year resident of Montana reports the income received while a Montana resident, plus any Montana-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
| New Jersey | Montana | |
|---|---|---|
| Taxes wages | Yes — graduated | Yes — graduated |
| Reciprocity partners | 1 (Form NJ-165) | 1 (Form MW-4) |
| Convenience rule | Only against convenience-rule states | No |
| Nonresident return | Form NJ-1040NR | Form 2 with the nonresident/part-year schedule |
| Part-year return | Form NJ-1040 (part-year resident) | Form 2 with the nonresident/part-year schedule |
| Credit for other-state tax | Schedule NJ-COJ | Form 2 (credit for income tax paid to another state) |
| Nonresident safe harbour | None published | None published |
| Local income tax | No | No |
| Revenue department | New Jersey Division of Taxation | Montana Department of Revenue |
| Last verified |
The other direction
Reversing the commute does not always reverse the answer. Living in Montana and working in New Jersey 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: New Jersey → MontanaBoth states — credit offsets the double tax
- Remote worker: New Jersey → MontanaHome state only
- 1099 contractor: New Jersey → MontanaHome state, plus the client state if you work there
Other New Jersey pairs
Questions people actually ask
I moved from New Jersey to Montana mid-year. Do I have to file in both states?
You file two part-year returns. New Jersey taxes the income you received while you lived there, Montana 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 New Jersey and Montana?
By when you received it, measured against the date your domicile actually changed. Income received while you were a New Jersey resident belongs on the New Jersey return and income received afterwards on the Montana 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 New Jersey and Montana rules on this page were last checked against New Jersey Division of Taxation and Montana 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.
- New Jersey Division of Taxation — individual income taxaccessed 2026-08-07
- New Jersey Division of Taxation — Convenience of the Employer Ruleaccessed 2026-08-07
- Montana Department of Revenue — individual income taxaccessed 2026-08-07