Thirty pairs of states tax a commuter's wages only at home

For the 2026 tax year, 15 states and the District of Columbia sit in 30 reciprocal pairings: a resident of one who works in the other owes the work state nothing on wages and hands the employer one certificate. An Indiana resident earning $65,000 in Kentucky, an agreement state, owes Indiana $1,888 in state income tax. Take the same job to Illinois, where Indiana has no agreement, and the state income tax bill becomes $3,073, all of it Illinois's.

A reciprocal agreement is a deal between two states that each will leave the other's residents' wages alone, so the worker files and pays only at home. It is narrow by design. Illinois's covers "wages, salaries, tips, and commissions" and no other income; Illinois lottery winnings and Illinois unemployment pay fall outside it.

Every agreement in force for 2026, and the form that claims it

The table is organized by the state where the job is, because that is the employer who needs the certificate. Each row is cited to that state's revenue department or its regulation; counting each pair once, the rows describe 30 pairings.

The District's row is not an agreement at all. D.C. Code § 1-206.02(a)(5) bars the Council from taxing the personal income of any nonresident, so a commuter from any state files the D-4A. Maryland and Virginia list the District among their reciprocal partners, which is what turns the arrangement into a two-way pairing.

Michigan is the one state with no certificate. Its Treasury "does not furnish non-residency certificates"; the employer drafts its own form or accepts a letter carrying the employee's name, legal address and Social Security number with a signed statement that the address is the employee's legal address (RAB 2017-13). The same bulletin dates each of Michigan's agreements, from Wisconsin's on October 1, 1967 to Minnesota's on January 1, 1984.

The conditions written into the fine print

Several pairings carry a test beyond residence, and failing it puts the work state's tax back on the paycheck.

• Daily commuting. Kentucky's agreement with Virginia "applies only to taxpayers who commute daily" (103 KAR 17:010). Virginia applies the same test to District and Kentucky residents working in Virginia (Virginia Tax).
• The 183-day abode test. Virginia exempts Maryland, Pennsylvania and West Virginia residents only if they are present 183 days or less, keep no Virginia abode and have only wage income there (Virginia Tax). Maryland's MW507 exemption lines ask the employee to certify keeping no Maryland abode for 183 days or more, yet the same form says a West Virginia domiciliary owes no Maryland tax on wages "regardless of the length of time" spent there.
• The monthly trip home. Minnesota's exemption requires a Michigan or North Dakota resident to return to that residence at least once a month; a "no" on line 3 of Form MWR ends the claim (Form MWR).
• The 20% S corporation owner. Kentucky's K-4 extends the Ohio exemption only to an employee who is not a 20%-or-greater shareholder-employee of an S corporation (Form K-4), and Pennsylvania has carved the same owner out of its Ohio agreement since January 1, 2004 (Pennsylvania DOR).
• The employer's consent. Pennsylvania's REV-419 stops Pennsylvania withholding only if the employer agrees to withhold and remit the home state's tax instead (Pennsylvania DOR).
• Annual renewal. Minnesota, Montana, Pennsylvania and Virginia each say the certificate is renewed every year (sources in the table).

Local income taxes ride outside the agreements. Indiana says its agreements "do not cover local income taxes", and its WH-47 leaves the employer responsible for any Indiana county tax (Form WH-47). Michigan's bulletin also excludes local taxes (RAB 2017-13). Maryland goes furthest: a Pennsylvania resident who files line 5 of the MW507 escapes Maryland's state tax but is still withheld at the rate of the Maryland county where the job is, unless the employee lives in York or Adams county or in a Pennsylvania locality that does not tax Maryland residents (Form MW507).

Without an agreement, the commuter pays the larger of the two state taxes

Where no agreement exists, two states have a claim on the same paycheck. The work state taxes the wages as nonresident income; the home state taxes all of its resident's income and then allows a credit for taxes paid to another state, a dollar-for-dollar offset against its own tax for the tax the other state charged on the same income. The credit is capped, so the double tax is relieved but the higher rate is not.

Indiana and Illinois are a real pair with no agreement: Illinois appears on Indiana's list of states with no agreement (Bulletin #28), and Indiana is absent from the four states named on Illinois's certificate (IL-W-5-NR). Run the $65,000 single filer with one Illinois job and no other income through the 2026 tables:

1. Illinois taxes first. A nonresident multiplies the exemption allowance by Illinois base income over total base income (Schedule NR, Step 5). With every dollar earned in Illinois that ratio is 1.000, so the nonresident return lands on the resident figure: 4.95% of $65,000 less the $2,925 exemption, or $3,073.
2. Indiana taxes everything. Its 2.95% flat rate on $65,000 less the $1,000 exemption is $1,888.
3. Indiana's credit takes the smallest of three figures: the tax paid to Illinois, Indiana's rate times the income both states taxed, and the Indiana tax due (Bulletin #28). The smallest is Indiana's own $1,888, so Indiana's state tax falls to zero.

The total is $3,073, against $1,888 for the same worker in Kentucky, where the agreement leaves the wages to Indiana alone. Generally, the arithmetic runs the other way when the home state charges more. Under Indiana's formula, an Indiana resident whose work state took the smaller amount gets that amount back as the credit and ends at Indiana's own figure, so the missing agreement costs a second return and a withholding refund rather than dollars.

Indiana runs a third arrangement with Arizona, Oregon and the District of Columbia, a "reverse credit": the state where the income is earned, not the home state, grants the credit, and the resident files the nonresident return there to claim it (Bulletin #28).

What the figures above include, and what TaxMath does not model

TaxMath's calculator computes resident returns only. Its state engine builds a hypothetical full-year resident return for each state over the same federal facts, with no nonresident or part-year return, no reciprocity and no credit for taxes paid to another state (design record ADR-0108). Every dollar figure in this article is a resident-return computation from the 2026 tables, a single filer with wages and the standard deduction. The Illinois figure stands in for a nonresident's only because Schedule NR's ratio is 1.000 when every dollar is earned in Illinois, and the method comes from the 2025 Schedule NR, the latest Illinois has published. The credit in step 3 is applied by hand from Indiana's published formula, not by the engine. Neither figure includes Indiana's county income tax, which the Indiana table excludes, or a city or occupational tax at the job.

For a commuter between two states, the numbers to compare are the two resident figures, which the calculator prices on your own wages: inside an agreement you pay your home state's, and without one, generally the larger of the two. For the Indiana resident with an Illinois offer, that gap is the distance between $1,888 and $3,073.