Meta description: California and Arizona do not have a reciprocal income tax agreement. Learn how state taxes, withholding, residency, and tax credits work for cross-border workers.
No. California and Arizona do not have a reciprocal income tax agreement. A worker who lives in one state and earns wages in the other may need to file a tax return in both, depending on where the work was performed and the worker’s residency. However, state tax credits may help prevent the same income from being taxed twice. Understanding the distinction between reciprocity, residency, income sourcing, and tax credits can make cross-border filing more straightforward.
What a State Tax Reciprocity Agreement Does
A state income tax reciprocity agreement generally allows residents of one state to pay income tax only to their home state on wages earned in a neighboring state. Without such an agreement, the work state may tax wages earned within its borders, while the home state may tax its resident’s income from all sources. The worker may then need to file returns in both states and claim an available credit.
Reciprocity is not the same as a tax credit. A reciprocity agreement changes which state has the right to tax certain wages. A credit is a tax benefit claimed on a return that may reduce tax owed to a resident state when another state has already taxed the same income.
California and Arizona have not established a general wage-tax reciprocity agreement. Therefore, the applicable rules usually depend on residency and where the employee physically performed the work—not simply on the location of the employer or the worker’s home.
How California and Arizona Tax Cross-Border Workers
Residents generally report income to their home state
California residents are generally subject to California income tax on income from all sources. Arizona residents are generally subject to Arizona income tax on income from all sources. This broad rule can apply even when a resident earns wages from an employer located in the other state.
For example, an Arizona resident employed by a California company does not automatically owe California income tax on every paycheck. The location where the employee performs services is important. If the employee works entirely from an Arizona home, those wages generally are not California-source wages merely because the employer is headquartered in California. Other facts and California-specific sourcing rules may affect the result.
Nonresidents may owe tax to the state where they work
A state can generally tax nonresidents on income sourced to that state. For wage earners, the physical location where services are performed is often central. A California resident who regularly works at an Arizona job site may have Arizona-source wages for the days worked in Arizona. An Arizona resident who performs services at a California workplace may have California-source wages for those workdays.
When an employee works in more than one state, the employer or employee may need to allocate compensation between states. Work calendars, time records, travel records, and payroll statements can help support that allocation. The precise calculation depends on the type of compensation and applicable state rules.
Remote Work Can Make State Sourcing More Complicated
Remote work does not always mean wages are taxed only where the employee’s home is located. The general starting point is where the services are performed, but California has rules that can affect nonresident employees working remotely for California employers.
Under California’s “convenience of the employer” rule, days worked outside California may still be treated as California workdays in certain circumstances when the employee’s services are for a California-based employer and the out-of-state work arrangement is for the employee’s convenience rather than the employer’s necessity. The facts matter, and exceptions may apply. Employees working remotely for California companies should review current Franchise Tax Board guidance or consult a qualified tax professional rather than assume that all home-office wages are outside California’s reach.
Arizona also applies source-of-income rules to nonresidents. A nonresident’s Arizona return generally concerns Arizona-source income, which may include compensation for services physically performed in Arizona. A person who moves during the year, splits workdays between states, or receives bonuses or equity compensation may need a more detailed allocation.
Tax Credits May Reduce Double Taxation
When both states tax the same income, the worker may be eligible for a credit on the resident-state return for income tax paid to the other state. The credit is generally limited; it does not necessarily reimburse every dollar paid to the work state or eliminate all differences between the two states’ tax bills.
- An Arizona resident: Arizona may allow a credit for qualifying net income taxes paid to another state on income included in Arizona income. Form 309 is used to calculate the Arizona credit for taxes paid to another state, subject to the form’s rules and limits.
- A California resident: California may allow a credit for qualifying income taxes paid to another state on income that is also taxed by California. The credit is generally claimed using Schedule S, subject to California’s requirements and limitations.
Typically, the credit is claimed on the resident-state return, and the nonresident return is filed in the state where the income was earned. The credit calculation can depend on the amount of tax paid, the income involved, and the resident state’s calculation of tax on that income. A tax credit is not the same as a refund of the other state’s withholding.
Filing order can matter. In many situations, a taxpayer first calculates the tax owed to the state where the work was performed, then uses the final tax information to determine the resident-state credit. Taxpayers should follow the current instructions for each state’s return, because forms and procedures can change.
Withholding Is Not the Same as Final Tax
Employers may withhold state income tax based on payroll records, the employee’s residence, the assigned work location, or information supplied by the employee. Withholding is an estimated payment toward tax; it does not by itself determine which state ultimately has the right to tax the income.
If payroll withholds California tax from an Arizona resident who performed all services in Arizona, the employee may need to file a California nonresident return to claim a refund, depending on the circumstances. Conversely, a worker who owes tax to a state but had too little withheld may owe a balance when filing.
Employees should check their pay stubs and state withholding elections after moving or changing work locations. California employees commonly use Form DE 4 to adjust California withholding. Arizona employees commonly use Form A-4. These forms guide withholding but do not replace the filing requirements for an individual income tax return.
Common California–Arizona Work Situations
| Situation | General tax consideration |
|---|---|
| Arizona resident works entirely in Arizona for a California employer | Wages generally are associated with the place services are performed. The employer’s California location alone does not automatically make all wages California-source; California’s remote-work rules and the specific facts should be checked. |
| Arizona resident works at a California job site | Wages for services performed in California may be California-source. The worker may need a California nonresident return and may be able to claim an Arizona credit for qualifying tax paid to California. |
| California resident works at an Arizona job site | Wages for services performed in Arizona may be Arizona-source. The worker may need an Arizona nonresident return and may be eligible to claim a California credit for qualifying Arizona tax. |
| Employee works in both states | Compensation may need to be allocated using workdays or another appropriate method. Records showing where services were performed are useful. |
| Person moves between California and Arizona during the year | Part-year resident returns may be required. Income earned before and after the move, and income sourced to either state, should be reviewed separately. |
This table describes common patterns, not a definitive tax result. Special rules may apply to stock compensation, bonuses, business income, military pay, or other kinds of income.
When a State Tax Return May Be Required
A worker may need to file a nonresident return in the state where the work was performed if that state’s filing rules apply. The worker may also have to file a resident or part-year resident return in the state of residence. Filing thresholds and requirements vary by state, income level, filing status, and tax year.
Filing can still be necessary when an employee expects a refund of state withholding. A return may also be needed to claim a credit on the home-state return or to report income correctly. Taxpayers should use the current instructions from the California Franchise Tax Board and the Arizona Department of Revenue to determine filing obligations.
Someone who lives in one state but works in the other should not assume that a small number of workdays automatically makes a return unnecessary. State thresholds and sourcing rules differ, and partial-year work can still create a filing obligation.
Records That Help Support a Cross-State Tax Return
Accurate records can help establish residency, work location, withholding, and the amount of income assigned to each state. Useful documents may include:
- Pay statements and year-end wage statements, including Form W-2.
- A calendar or timesheet showing workdays in California, Arizona, and other locations.
- Travel records, work schedules, and employer documentation of assigned work locations.
- Lease, mortgage, utility, and moving records when residency changes during the year.
- Copies of filed state returns and proof of taxes paid when claiming a credit.
Employees who receive stock options, restricted stock, commissions, or deferred compensation should keep grant and vesting records as well. These forms of compensation may be sourced over a period of time and may not follow the same simple workday calculation as regular wages.
Other Agreements Are Separate From Income Tax Reciprocity
The phrase “reciprocal agreement” can refer to arrangements beyond individual income taxes, including agreements involving vehicle registration, professional licensing, law enforcement, or other public services. The absence of a California–Arizona wage-tax reciprocity agreement does not establish whether a particular agreement exists in another area.
Likewise, tax rules for sales tax, business activity, unemployment insurance, and workers’ compensation are distinct from individual income tax reciprocity. A worker should not use an answer about wage taxes to make assumptions about those separate obligations.
How to Check the Rules for a Specific Situation
For a cross-border employee, the key questions are usually where the employee lived during the tax year, where the services were physically performed, whether the employee worked remotely for a California employer, and how much tax each state withheld. The answers help determine whether a resident, part-year resident, or nonresident return may be required.
Official guidance is available from the California Franchise Tax Board and the Arizona Department of Revenue. Relevant materials include California’s nonresident and part-year resident guidance, Schedule S instructions, Arizona Form 309 instructions, and each state’s current filing requirements. Because residency and sourcing depend on facts, complicated cases may warrant advice from a tax professional familiar with both states.
Bottom line: California and Arizona do not have a general reciprocal income tax agreement. Cross-border workers may owe tax to the state where they perform services and may also report income to their resident state. A qualifying tax credit can reduce double taxation, but workers should verify sourcing, withholding, and filing requirements for their particular circumstances.