Earning income in one state while living in (or being taxed as a resident of) another creates a real risk of paying state income tax twice on the same dollars — the credit for taxes paid to another state is the standard mechanism most states use to prevent that outcome, though it doesn't always eliminate the burden entirely.
The Basic Problem: Two States, One Dollar of Income
Many states tax non-residents on income earned within their borders (from a job physically performed there, or from a business operating there) while separately taxing their own residents on all income regardless of where it was earned. Someone who lives in State A but works in State B can end up with State B taxing the wages as nonresident income, and State A also taxing the same wages as resident income — without a credit mechanism, that same income would be taxed twice.
How the Credit Typically Works
Most states with an income tax allow their own residents a credit for income tax paid to another state on income also taxed by the resident state. In the common commuter scenario above, State A (the resident state) would generally grant a credit against its own tax for whatever tax was paid to State B on the same income — effectively making the resident state's tax the "backstop" only for whatever exceeds what the work state already collected.
The Cap: Usually Limited to Your Resident State's Rate
The credit is typically capped at the amount of tax your resident state would have imposed on that same income — not necessarily the full amount you actually paid to the other state. If the work state's tax rate is higher than your resident state's rate, you may not get a full credit for the difference, effectively paying the higher of the two states' rates on that income overall (not the sum of both, but not simply the lower rate either). If the work state's rate is lower than your resident state's rate, your resident state typically still collects the difference up to its own rate.
💡 This is why moving from a no-income-tax state to a state with income tax (or vice versa) for work while keeping residency in your original state matters so much for your total state tax burden — the credit generally caps out at your resident state's rate, so working in a much higher-tax state than where you live doesn't automatically save you money the way you might assume.
Reciprocity Agreements: A Simpler Alternative for Some Neighboring States
A number of neighboring states have negotiated reciprocity agreements specifically for commuters, under which the work state agrees not to tax nonresident wage income from residents of the reciprocal partner state at all — instead of paying tax to the work state and then claiming a credit on your resident return, you simply don't owe the work state anything in the first place (though you may need to file a specific exemption form with your employer to stop withholding for the work state). Reciprocity agreements are typically limited to wage income specifically and don't extend to business income, capital gains, or other income types — check whether your specific pair of states has such an agreement, since it isn't universal even among adjacent states.
This Doesn't Eliminate the Filing Burden
Even with the credit working correctly to prevent double taxation, you'll generally still need to file a nonresident return in the work state (reporting and paying tax on the income earned there) in addition to your resident state return (where you claim the credit) — the credit prevents double taxation of the dollars, but it doesn't reduce the number of state returns you need to prepare unless a reciprocity agreement specifically eliminates the work-state filing requirement.
A Worked Example
Business Income and Nonresident Filing Requirements
Self-employed people and business owners face this same double-taxation risk on business income sourced to a different state than their residence — the same credit mechanism generally applies, though determining exactly how much business income is "sourced" to each state can be considerably more complex than the wage-earner scenario above, particularly for a self-employed consultant or contractor doing work for clients across multiple states.
A Worked Example
Someone lives in a state with a 5% flat income tax and commutes to work in a neighboring state with a 6% flat rate (no reciprocity agreement between the two). On $80,000 of wages, they pay $4,800 to the work state (6%). Their resident state calculates its own tax on the same $80,000 at 5% ($4,000), then grants a credit — capped at their own $4,000 liability — for the tax paid to the work state. Since the work-state tax ($4,800) exceeds the resident-state liability ($4,000), the credit fully offsets the resident-state tax, and they owe nothing additional to their resident state on this income, but they've still effectively paid the higher 6% rate overall rather than their home state's lower 5% rate.
Common Questions
Does this credit apply to income from a state with no income tax? There's nothing to credit if the work state doesn't tax the income in the first place — the credit only matters when both states are actually taxing the same income.
What about remote work across state lines? This has become a much more complicated area since remote work became widespread — the relevant question shifts from "where did you physically work" to specific state nexus and "convenience of the employer" rules that vary significantly by state; check current guidance for your specific state pair.
Do I need to file the work-state return even if the credit fully offsets my resident-state liability? Generally yes, if the work state requires nonresidents to file above certain income thresholds — the credit is claimed on your resident return, but doesn't eliminate a separately required nonresident filing.
💡 Check both your work state's and your resident state's tax rates to estimate your combined state tax burden before assuming the credit fully neutralizes any rate difference.