THE CREDIT FOR TAXES PAID TO OTHER STATES is the principal mechanism by which states prevent DOUBLE TAXATION of multistate income earned by their residents. CORE PRINCIPLE: when a resident of State A earns income sourced to State B, State B taxes it as nonresident source income AND State A taxes it as part of resident worldwide income. To avoid double tax, State A typically allows a CREDIT against its tax for taxes paid to State B on the same income. CONSTITUTIONAL FRAMEWORK - Comptroller of the Treasury of Maryland v. Wynne, 575 U.S. 542 (2015): US Supreme Court held that a state income tax scheme that taxes residents on in-state and out-of-state income violates the Dormant Commerce Clause when it does NOT provide residents a FULL CREDIT for income taxes paid to other states. Wynne struck down Maryland's failure to allow credit against COUNTY income tax for taxes paid to other states. CREDIT MECHANICS - typically limited to LESSER of: (a) ACTUAL tax paid to other state on doubly-taxed income; OR (b) RESIDENT STATE TAX that would have applied to the same income at resident-state rates. This "lesser-of" limitation means residents of high-tax states (NY, CA) typically receive full credit when working in lower-tax states; residents of lower-tax states (FL, TX - though these have no income tax) face limited credit utility. STATE-BY-STATE VARIATIONS: most states (38 of 41 income-tax states) follow standard credit mechanism. ALABAMA, OREGON, INDIANA, NEW JERSEY have variations on credit computation. PENNSYLVANIA flat-rate credit. NJ, MO certain reciprocal arrangements. WORKING IN MULTIPLE NONRESIDENT STATES: resident state typically allows credit for each nonresident state tax paid; credit computed separately per state under each state's rules. CREDIT FOR PASS-THROUGH ENTITY TAX (PTE) - states' SALT cap workarounds since 2018 - PTE pays state tax at entity level; resident shareholders/partners receive resident-state credit for entity-level state tax paid; complex coordination per state (see PTE guide). CHARACTER LIMITATION - credit usually limited to income tax paid; not for sales tax, property tax, or other-state franchise/business taxes. NONREFUNDABLE - credit cannot exceed resident state tax; excess "wasted" if other-state tax higher. RECIPROCAL AGREEMENTS - certain state pairs (PA-NJ, PA-OH, VA-DC, MD-DC) have reciprocal arrangements eliminating nonresident-state taxation; resident state taxes alone with no credit needed.
Core mechanism: Resident state taxes worldwide income; allows credit for taxes paid to other states on doubly-taxed income. Prevents economic double taxation.
Limit: Lesser of (a) actual tax paid to other state on the doubly-taxed income, or (b) resident state tax on the same income at resident rates. Residents of high-tax states benefit most.
Wynne (2015): US Supreme Court held failure to provide full credit violates Dormant Commerce Clause; Maryland struck down for not allowing credit against county income tax.
Source-state rule: Income taxed only where sourced - employee in office state, property in property location, business activities in business location. Resident state credits prevent overlap.
Reciprocal pairs: PA-NJ, PA-OH, PA-VA-DC, MD-DC. Resident-state tax only; no nonresident return or credit needed. Most states no reciprocal.
| Constitutional Element | Detail |
|---|---|
| Comptroller v. Wynne, 575 US 542 (2015) | US Supreme Court (5-4) held that Maryland's income tax violates Dormant Commerce Clause by NOT providing residents full credit for taxes paid to other states. MD allowed credit against state income tax but NOT against county income tax (which functioned as state-level tax). Court invalidated the credit limitation as discriminatory against interstate commerce |
| Internal Consistency Test | Wynne test - hypothetically if every state had the same tax scheme, would it impose multiple taxation on interstate commerce? MD scheme failed internal consistency because if every state did what MD did, interstate income would be taxed multiple times |
| External Consistency | Tax must reflect a reasonable relationship to instate activity; broader analysis |
| Dormant Commerce Clause | State tax cannot discriminate against interstate commerce or impose burdens that interstate commerce would not face |
| Practical effect of Wynne | States must provide full credit for taxes paid to other states on the same income to avoid Dormant Commerce Clause violation; resolved many state-specific issues |
| Pennsylvania response | PA had similar split between state and local Philadelphia wage tax; allowed credit only against state, not Philadelphia tax; subject to similar Dormant Commerce Clause challenges |
| Limitation issues post-Wynne | Pre-Wynne, many state credit schemes limited credit to "income tax" excluding county/city taxes; Wynne required broader credit |
| Convenience rule states | Wynne raised but did not directly address convenience-of-employer rule constitutionality; states like NY still maintain convenience rules with credits available |
| Internal consistency for source rule | State source rules generally must pass internal consistency - cannot tax interstate activity in ways residents of other states would face same multiplication |
| Compensating tax doctrine | Oregon Waste Systems v. Department of Environmental Quality, 511 US 93 (1994) - independent taxes on intrastate and interstate commerce considered "compensatory" if rough equivalents |
| Credit Element | Detail |
|---|---|
| Resident state imposition | Resident state taxes WORLDWIDE income at full resident rates |
| Nonresident state imposition | Nonresident state taxes ONLY income sourced to that state |
| Credit purpose | Prevent same income from being taxed by both states; effectively allows source state to tax first, resident state takes residual |
| Credit formula | Resident state credit = LESSER of: (a) actual income tax paid to other state on income that is also resident-state taxable; OR (b) resident state tax that would apply to that income (computed at resident state rates) |
| Where high-tax resident | NY resident (10.9% top rate) working in CA (13.3% top rate) - credit limited to NY rate on CA-source income, even though CA tax was higher. Effectively pays NY tax on rate differential |
| Where low-tax resident | NJ resident (10.75% top rate) working in PA (3.07% flat rate) - PA tax is low; NJ provides credit but PA tax was small; NJ still collects most of the tax |
| FL/TX/no-income-tax residents | No resident state tax to credit against; pay nonresident state tax in full with no offset; FL/TX residents in NY pay full NY nonresident tax |
| Refundability | Credit is generally NONREFUNDABLE - cannot exceed resident state tax; excess "wasted" |
| Multi-state credit | Resident with income from multiple states - separate credit per source state; subject to overall limitation |
| Apportionment limitation | Credit must relate to income that BOTH states tax; income that resident state would not tax (e.g., source-only income that fails resident-state nexus) gets no credit |
| State | Credit Detail |
|---|---|
| New York §620 | Standard mechanism; credit for income taxes paid to other state or DC on income also taxed by NY; Form IT-112-R for resident credit; not available for nonresidents (they file IT-203 as nonresident only) |
| California §18001 | Standard credit for taxes paid to other states by CA resident; complex apportionment of CA-tax-equivalent on doubly-taxed income; FTB Pub. 1031 |
| New Jersey §54A:4-1 | Standard credit for income taxes paid to other state on income also taxed by NJ; modified treatment for NY convenience-rule tax on NJ residents |
| Connecticut §12-704 | Standard mechanism; 2018 amendments specifically addressed NY convenience-rule tax allowing credit; CT Special Notice 2018(5) |
| Pennsylvania §301 (resident credit) | PA flat 3.07% rate; credit mechanism for taxes paid to other states; complicated by Philadelphia wage tax credit issues |
| Massachusetts c. 62 §6(a) | Standard credit; Schedule OJC for credit computation |
| Illinois §901 | Credit for income tax paid to another state; Schedule CR |
| Ohio §5747.05(B) | Credit for tax paid to another state; reciprocal agreements with several states |
| Texas, Florida, Nevada, Wyoming, South Dakota, Washington, Alaska, Tennessee, New Hampshire | No state income tax - no resident-state credit applicable; multistate workers in these states pay nonresident-state tax with no offset |
| Indiana | Variations on credit computation - county income tax issues post-Wynne (similar to MD issues) |
| Alabama | Some variations for nonemployer/business income credit calculations |
| Oregon | OR §316.082 - some unique computational rules |
| Maryland post-Wynne | Expanded credit to include county tax for taxes paid to other states (responsive to Wynne) |
| Reciprocal Pair | Effect |
|---|---|
| Pennsylvania - New Jersey | Residents of one state working in the other taxed ONLY by their resident state; no nonresident-state return required. Reciprocal Agreement since 1977. Form REV-419 (PA) or NJ-165 (NJ) certifies residency to employer |
| Pennsylvania - Ohio | Similar reciprocal arrangement; PA-OH residents pay resident-state only on wages |
| Pennsylvania - Maryland | Reciprocal for wages |
| Pennsylvania - Indiana | Reciprocal |
| Pennsylvania - Virginia | Reciprocal |
| Pennsylvania - West Virginia | Reciprocal |
| DC - VA - MD | Reciprocal for wages; resident-state only tax; District residents and VA/MD residents commuting |
| Wisconsin - Illinois, Indiana, Kentucky, Michigan | Reciprocal arrangements |
| Michigan - Indiana, Ohio, Wisconsin, Kentucky, Minnesota, Illinois | Reciprocal |
| Iowa - Illinois | Reciprocal |
| Kentucky - Indiana, Michigan, Ohio, Virginia, West Virginia, Wisconsin, Illinois | Multiple reciprocal arrangements |
| Minnesota - North Dakota, Michigan, Wisconsin | Reciprocal |
| Montana - North Dakota | Reciprocal |
| NY, CA, MA, NJ (most) | NO reciprocal agreements; standard credit mechanism applies |
| Effect of reciprocal | Employer withholds for employee's resident state only; no nonresident state return; no credit needed; simplifies multistate W-2 employees in these state pairs |
Facts: Frank is a NJ resident employed by NYC-based law firm. 2026 total income $400,000 all wages. Working day allocation: 224 NY working days / 240 total = 93.33% NY source (per separate guide; assumes convenience rule applied to home days).
NY source wages: $400,000 × 0.9333 = $373,333
Non-NY wages: $26,667 (firm-required out-of-state travel)
2026 NY top marginal rate: 10.9%; 2026 NJ top marginal rate: 10.75%
Step 1: NY nonresident tax computation:
Frank files Form IT-203 nonresident return
NY income: $373,333 (CA source); compute NY tax as nonresident
NY tax (illustrative): approximately $36,500 on $373,333 NY source income
Step 2: NJ resident tax computation:
Frank files NJ-1040 as resident
NJ taxes worldwide income $400,000 at NJ rates
NJ tax before credit (illustrative): approximately $38,000 on $400,000 worldwide
Step 3: NJ resident credit §54A:4-1:
Doubly-taxed income (NY source income $373,333 also included in NJ worldwide income): $373,333
NJ tax that would apply at NJ rates to $373,333: approximately $35,500
NY actual tax paid on $373,333: approximately $36,500
NJ credit = LESSER of: (a) $36,500 (NY actual), or (b) $35,500 (NJ would-have-imposed) = $35,500
NJ tax after credit: $38,000 - $35,500 = $2,500
Step 4: Total state tax:
NY: $36,500
NJ (after credit): $2,500
Total state tax: $39,000
Effective rate: $39,000 / $400,000 = 9.75%
Step 5: Without convenience rule (hypothetical):
If NY did not have convenience rule, Frank's home-office days would be non-NY days. Say only 100 NY working days out of 240; NY source = 41.67%; NY source income = $166,667.
NY tax: approximately $14,500 on $166,667
NJ tax on $400,000 worldwide: $38,000
NJ credit limited to NJ tax on doubly-taxed $166,667 = approximately $14,800; LESSER of $14,500 (NY actual) or $14,800 (NJ would-have) = $14,500
NJ after credit: $38,000 - $14,500 = $23,500
Total state tax: $14,500 + $23,500 = $38,000
Effective: 9.5% (similar to actual; NJ collects the residual)
Observation:
Where resident state rate (NJ 10.75%) is similar to nonresident state rate (NY 10.9%), credit mechanism essentially makes resident state the residual tax authority on local rate differential. The total combined state tax burden approximates resident-state-only tax in scenarios where convenience rule doesn't apply. Where it does apply, the tax burden shifts based on which state's rate is higher.
What if Frank were FL resident:
FL has no income tax. Frank pays only NY nonresident tax. No credit available since FL has no tax to apply credit against. Total state tax: $36,500. Less than NJ resident scenario above because FL doesn't collect on the income beyond what NY collected. Why HNW often move to FL.
Credit generally limited to income taxes paid to other states; not sales tax, property tax, franchise taxes, gross receipts taxes. Practitioner crediting sales tax misapplies; doubles tax exposure.
PTE elective taxes (SALT cap workarounds) - entity pays state tax; resident-state credit for PTE tax paid varies by state. NY, NJ, CA each have different mechanics. Practitioner not coordinating PTE election with resident state credit may double-tax or miss optimization.
Credit limited to LESSER of actual nonresident tax OR resident-state tax on same income. Practitioner claiming full nonresident tax when resident-state rate is lower over-credits; refund denied on audit.
Only income TAXED BY BOTH STATES qualifies for credit. Income taxable only in source state (because resident state would not tax) doesn't qualify. Practitioner including source-only income in credit base overstates.
Most credits are nonrefundable. If nonresident tax exceeds resident-state tax on doubly-taxed income, the excess is "wasted" - no refund. Practitioner not advising client on this asymmetry may miss planning opportunities (e.g., reducing nonresident state taxable income through deductions).
NY convenience rule tax historically denied credit by CT (CT considered the income CT-source); 2018 CT statute now allows credit. Practitioner advising CT resident must verify post-2018 CT credit treatment.
Resident with income from multiple nonresident states - compute credit separately per state. Practitioner aggregating may miscalculate; each state's credit subject to that state's rate computation.
If state pair has reciprocal (PA-NJ, etc.), no nonresident state return required; resident state taxes only. Practitioner filing nonresident state return where reciprocal applies creates unnecessary work; or withholding agent's failure to apply reciprocal exemption may require refund claim.
NY resident credit requires Form IT-112-R with documentation of other-state tax paid. Practitioner attaching incomplete documentation invites audit denial; copies of other-state return required.
Some states require credit based on "tax imposed" not "tax paid" - difference includes withholding excess, refunds, amendments. Practitioner using withholding amount instead of actual tax may misstate.
NYC nonresident tax repealed 1999; only NY State tax for nonresidents now. Philadelphia wage tax - controversial credit treatment; post-Wynne credits expanded. Practitioner must check local-tax credit availability separately.
Many states allow composite filing for nonresident pass-through owners. Composite return effectively pays nonresident tax on owner's behalf. Resident state typically allows credit for tax paid via composite; but coordinate with PTE election.
Resident state estimated tax often paid before nonresident state filing; can create timing mismatch. Practitioner not coordinating estimated payments across states may trigger underpayment penalties.
Multistate NOL coordination complex; resident state NOL may not align with nonresident state NOL. Practitioner using federal NOL without state-by-state apportionment may miscalculate.
State tax deduction limited to $40,000 SALT cap (per OBBBA). Pre-cap, multistate income led to larger SALT deductions; post-cap, planning value reduced. Practitioner overlooking SALT cap interaction in multistate planning misses material consideration.
NIIT (federal §1411) is federal tax; not state; not in credit calculation. Practitioner including NIIT in resident-state credit miscomputes.
Some states have different tax years or fiscal-year reporting (rare for individuals; common for businesses). Practitioner not aligning tax years across states may miscompute credit timing.
Some states allow carryforward of unused credit (rare for individual income tax). Practitioner not researching state-specific carryforward rules may waste excess credit.
Primary authority: Comptroller of the Treasury of Maryland v. Wynne, 575 U.S. 542 (2015) (full credit for taxes paid to other states required under Dormant Commerce Clause). U.S. Const. art. I §8 cl. 3 (Commerce Clause). Oregon Waste Systems v. Department of Environmental Quality, 511 U.S. 93 (1994) (internal consistency / compensatory tax doctrine). South Dakota v. Wayfair, 138 S. Ct. 2080 (2018) (state tax nexus expansion under economic presence). NY Tax Law §620 (resident credit for income taxes paid to other states). NY Form IT-112-R (Resident Credit). CA Revenue and Taxation Code §18001 (resident credit for taxes paid to other states). California Form Schedule S (Other State Tax Credit). FTB Pub. 1031 (Guidelines for Determining Resident Status). NJ Revenue Statute §54A:4-1 (resident credit for taxes paid to other states). NJ Schedule NJ-COJ (Other Jurisdiction Credit). NJ Schedule NJ-DOP. CT Gen. Stat. §12-704 (resident credit for tax paid to other state; 2018 amendments for NY convenience-rule tax). CT Schedule 2 (Credit for Income Taxes Paid to Qualifying Jurisdictions). CT Special Notice 2018(5) (NY convenience rule credit treatment). PA Tax Reform Code §301 (resident credit). PA Schedule G-L (Resident Credit for Taxes Paid to Other States). Philadelphia tax credit issues post-Wynne. MA Gen. Laws c. 62 §6(a) (resident credit). MA Schedule OJC (Credit for Other Jurisdiction Tax). Illinois 35 ILCS 5/901 (resident credit). IL Schedule CR (Credit for Tax Paid to Other States). Ohio §5747.05(B) (resident credit). OH Schedule of Credits. Pennsylvania-New Jersey Reciprocal Agreement (1977; PA Form REV-419, NJ Form NJ-165). Pennsylvania-Ohio Reciprocal Agreement. Pennsylvania-Maryland Reciprocal Agreement. Pennsylvania-Indiana Reciprocal Agreement. Pennsylvania-Virginia Reciprocal Agreement. Pennsylvania-West Virginia Reciprocal Agreement. DC-Virginia-Maryland Reciprocal Agreement. Wisconsin reciprocal agreements with IL, IN, KY, MI. Michigan reciprocal agreements. Kentucky reciprocal agreements with IN, MI, OH, VA, WV, WI, IL. Minnesota reciprocal agreements with ND, MI, WI. Iowa-Illinois Reciprocal Agreement. Montana-North Dakota Reciprocal Agreement. Indiana county tax post-Wynne treatment. Maryland post-Wynne credit expansion (Tax Court of Maryland and SB 763 (2015) - response to Wynne). Pass-Through Entity Elective Tax statutes (state-by-state): NY Tax Law §860-866 (PTET); NJ Pass-Through Business Alternative Income Tax Act; CA AB 150 (2021); IL P.A. 102-0658 (2021); MA c. 63D PTE election; and approximately 35 other states. IRC §164 (state and local tax deduction). IRC §164(b)(6) ($10,000 SALT cap; modified to $40,000 by OBBBA P.L. 119-21). IRS Notice 2020-75 (PTE election preserves federal deduction; pre-TCJA SALT cap workaround). Forms - varies by state - IT-112-R (NY), Schedule S (CA), Schedule NJ-COJ (NJ), Schedule 2 (CT), Schedule G-L (PA), Schedule OJC (MA), Schedule CR (IL), Schedule of Credits (OH).