Moved from Idaho to District of Columbia Mid-Year: Which State Tax Returns Do You File?
Answer
Two returns, split at the move date. Idaho and District of Columbia 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 · 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 · District of ColumbiaForm D-40 (part-year resident)
File a District of Columbia part-year return covering the months you lived in District of Columbia. A part-year resident of District of Columbia reports the income received while a District of Columbia resident, plus any District of Columbia-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 | District of Columbia | |
|---|---|---|
| Taxes wages | Yes — flat | Yes — graduated |
| Reciprocity partners | None | 2 (Form D-4A) |
| Convenience rule | No | No |
| Nonresident return | Form 43 | None — nonresidents exempt |
| Part-year return | Form 43 (part-year resident) | Form D-40 (part-year resident) |
| Credit for other-state tax | Form 39NR | Schedule U (Form D-40) |
| Nonresident safe harbour | None published | Not applicable |
| Local income tax | No | No |
| Revenue department | Idaho State Tax Commission | District of Columbia Office of Tax and Revenue |
| Last verified |
The other direction
Reversing the commute does not always reverse the answer. Living in District of Columbia 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 → District of ColumbiaNonresidents are exempt by statute
- Remote worker: Idaho → District of ColumbiaHome state only
- 1099 contractor: Idaho → District of ColumbiaHome state, plus the client state if you work there
Other Idaho pairs
Questions people actually ask
I moved from Idaho to District of Columbia mid-year. Do I have to file in both states?
Two returns, split at the move date. Idaho and District of Columbia 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 Idaho and District of Columbia?
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 District of Columbia 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 District of Columbia rules on this page were last checked against Idaho State Tax Commission and District of Columbia Office of Tax and 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
- District of Columbia Office of Tax and Revenue — individual income taxaccessed 2026-08-07