Moved from Pennsylvania to Montana Mid-Year: Which State Tax Returns Do You File?
Answer
Two returns, split at the move date. Pennsylvania and Montana both tax residents, so each takes the portion of the year you were one. This is a residency question rather than a sourcing question — reciprocity agreements and convenience rules have nothing to do with it.
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 · PennsylvaniaForm PA-40 (part-year resident)
File a Pennsylvania part-year return covering the months you lived in Pennsylvania. A part-year resident of Pennsylvania reports the income received while a Pennsylvania resident, plus any Pennsylvania-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
| Pennsylvania | Montana | |
|---|---|---|
| Taxes wages | Yes — flat | Yes — graduated |
| Reciprocity partners | 6 (Form REV-419) | 1 (Form MW-4) |
| Convenience rule | Yes — general rule | No |
| Nonresident return | Form PA-40 (nonresident) | Form 2 with the nonresident/part-year schedule |
| Part-year return | Form PA-40 (part-year resident) | Form 2 with the nonresident/part-year schedule |
| Credit for other-state tax | Schedule G-L | Form 2 (credit for income tax paid to another state) |
| Nonresident safe harbour | None published | None published |
| Local income tax | Yes | No |
| Revenue department | Pennsylvania Department of Revenue | Montana Department of Revenue |
| Last verified |
The other direction
Reversing the commute does not always reverse the answer. Living in Montana and working in Pennsylvania 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: Pennsylvania → MontanaBoth states — credit offsets the double tax
- Remote worker: Pennsylvania → MontanaHome state only
- 1099 contractor: Pennsylvania → MontanaHome state, plus the client state if you work there
Other Pennsylvania pairs
Questions people actually ask
I moved from Pennsylvania to Montana mid-year. Do I have to file in both states?
Two returns, split at the move date. Pennsylvania and Montana both tax residents, so each takes the portion of the year you were one. This is a residency question rather than a sourcing question — reciprocity agreements and convenience rules have nothing to do with it.
How do I split my income between Pennsylvania and Montana?
By when you received it, measured against the date your domicile actually changed. Income received while you were a Pennsylvania resident belongs on the Pennsylvania 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 Pennsylvania and Montana rules on this page were last checked against Pennsylvania Department of Revenue 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.
- Pennsylvania Department of Revenue — individual income taxaccessed 2026-08-07
- Pennsylvania — Form REV-419accessed 2026-08-07
- Pennsylvania Personal Income Tax Guide — Income Subject to Tax Withholdingaccessed 2026-08-07
- Montana Department of Revenue — individual income taxaccessed 2026-08-07