1099 Contractor in South Dakota with a Idaho Client: Where Do You File?
Answer
Idaho only, and only for on-site work. Nothing is withheld from a 1099, and South Dakota levies no income tax, so the single question is whether any of the services were performed in Idaho. If none were, no Idaho nonresident return is required.
Last verified
The most common contractor worry — that invoicing an out-of-state client creates a filing obligation there — is usually unfounded. What creates the obligation is physical presence, and South Dakota residents have no home-state return in any case.
Idaho publishes no de minimis day count or dollar floor for nonresidents. Any Idaho-source wage income above the state's general filing threshold requires a nonresident return, and that threshold is reset each year — check the current figure on the Idaho State Tax Commission nonresident instructions before filing.
What you file
- 1Nonresident return · IdahoForm 43
File a Idaho nonresident return only for income from services you physically performed in Idaho. South Dakota does not tax wage or self-employment income.
The two states, side by side
| South Dakota | Idaho | |
|---|---|---|
| Taxes wages | No | Yes — flat |
| Reciprocity partners | None | None |
| Convenience rule | No | No |
| Nonresident return | Not applicable | Form 43 |
| Credit for other-state tax | No income tax | Form 39NR |
| Nonresident safe harbour | Not applicable | None published |
| Local income tax | No | No |
| Revenue department | South Dakota Department of Revenue | Idaho State Tax Commission |
| Last verified |
The other direction
Reversing the commute does not always reverse the answer. Living in Idaho and working in South Dakota gives:Home state only — estimated payments.
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: South Dakota → IdahoWork state only
- Remote worker: South Dakota → IdahoNo state income tax on your wages
- Moved mid-year: South Dakota → IdahoOne part-year return — the state you moved to
Other South Dakota pairs
Questions people actually ask
I live in South Dakota and my client is in Idaho. Do I have to file a Idaho tax return?
Idaho only, and only for on-site work. Nothing is withheld from a 1099, and South Dakota levies no income tax, so the single question is whether any of the services were performed in Idaho. If none were, no Idaho nonresident return is required.
Do reciprocity agreements help a 1099 contractor?
No. Every state reciprocity agreement in the country is an arrangement about wage withholding between two revenue departments, and a 1099 has no withholding to switch off. Whether South Dakota and Idaho hold an agreement makes no difference to a self-employed filer — sourcing rules decide the answer instead.
How current is this?
The South Dakota and Idaho rules on this page were last checked against South Dakota Department of Revenue and Idaho State Tax Commission 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.
- South Dakota Department of Revenue — individual income taxaccessed 2026-08-07
- Idaho State Tax Commission — individual income taxaccessed 2026-08-07