1099 Contractor in Delaware with a Mississippi Client: Where Do You File?
Answer
Two possible returns, one certainty. The certainty is Delaware, which taxes residents on all self-employment income and expects quarterly estimated payments. The possibility is Mississippi, which taxes nonresidents on services actually performed inside the state — invoices sent there do not count.
Last verified
The client's location is the wrong thing to track. What matters is where you were sitting when you did the work — which is why a contractor's exposure to Mississippi is measured in days on the ground rather than in invoices sent.
Mississippi publishes no de minimis day count or dollar floor for nonresidents. Any Mississippi-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 Mississippi Department of Revenue nonresident instructions before filing.
What you file
- 1Quarterly estimated payments · Delaware
Make quarterly estimated payments to Delaware Division of Revenue on your full self-employment income — nothing is withheld from a 1099.
- 2Nonresident return · MississippiForm 80-205
File a Mississippi nonresident return only if you performed services inside Mississippi. Mississippi publishes no de minimis day count or dollar floor for nonresidents. Any Mississippi-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 Mississippi Department of Revenue nonresident instructions before filing.
- 3Resident return · DelawareSchedule I (Form PIT-RES)
File the Delaware resident return last and claim the credit for any tax paid to Mississippi.
The two states, side by side
| Delaware | Mississippi | |
|---|---|---|
| Taxes wages | Yes — graduated | Yes — flat |
| Reciprocity partners | None | None |
| Convenience rule | Yes — general rule | No |
| Nonresident return | Form PIT-NON | Form 80-205 |
| Credit for other-state tax | Schedule I (Form PIT-RES) | Form 80-160 |
| Nonresident safe harbour | None published | None published |
| Local income tax | Yes | No |
| Revenue department | Delaware Division of Revenue | Mississippi Department of Revenue |
| Last verified |
The other direction
Reversing the commute does not always reverse the answer. Living in Mississippi and working in Delaware gives:Home state, plus the client state if you work there.
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: Delaware → MississippiBoth states — credit offsets the double tax
- Remote worker: Delaware → MississippiHome state only
- Moved mid-year: Delaware → MississippiTwo part-year returns
Other Delaware pairs
Questions people actually ask
I live in Delaware and my client is in Mississippi. Do I have to file a Mississippi tax return?
Two possible returns, one certainty. The certainty is Delaware, which taxes residents on all self-employment income and expects quarterly estimated payments. The possibility is Mississippi, which taxes nonresidents on services actually performed inside the state — invoices sent there do not count.
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 Delaware and Mississippi hold an agreement makes no difference to a self-employed filer — sourcing rules decide the answer instead.
How current is this?
The Delaware and Mississippi rules on this page were last checked against Delaware Division of Revenue 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.
- Delaware Division of Revenue — individual income taxaccessed 2026-08-07
- Mississippi Department of Revenue — individual income taxaccessed 2026-08-07