If an employer has operations in more than one state, income tax might need to be withheld for multiple states. In fact, at times the employer might need to withhold income tax for multiple states from the wages of one employee. Withholding can become complicated when an employee lives in one state and works in another or performs services in more than one state.
Which state income tax to withhold?
As a starting point, the default rule of state income tax withholding is to withhold income tax for the state in which services are performed (the work state). Almost all states require employers to withhold tax from employee wages earned for work performed in that state, even for nonresidents. The analysis need go no further if the employee lives and works in one state. Also remember withholding is not required for the nine states that do not have a state income tax: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming.
An employee's state of residence must be determined because a resident is subject to the laws of that state, including its income tax laws. States have the power to tax all income of state residents, even income earned for work performed in a different state. State definitions of residency vary, so state laws and regulations must be consulted when making the determination.
An employer might be required to withhold income tax from wages for an employee's state of residence, even if the employee does not perform services there if the employer has a business presence or operations in that state, also referred to as nexus. The presence of a business location, such as an office, store, or factory in the state will create nexus there, as will the mere entry of an employee to make a sale or perform a service call. Additionally, an employee working remotely from his or her state of residence on an occasional basis might be enough of a business presence to create nexus.
During the COVID-19 public health crisis, many state tax agencies have issued guidance waiving nexus during the emergency period if it would have been established by the presence of resident employees working temporarily from home solely due to the pandemic. Most state guidance goes on to say nexus might be established in the future if the remote work continues beyond the emergency period. See APA's COVID-19 Payroll Resource Center for additional information.
When two states have a reciprocal agreement for tax purposes, it makes things administratively easier for the employer by allowing it to withhold only for the state of residence.
Credits against resident state income tax liability
Nonresident employees subject to state income taxation could qualify for credit against their resident state income tax liability for amounts paid to other states. This does not apply if the employee is a resident of a state without an income tax.
State nonresident taxation thresholds
Some states do not require an employer to withhold tax from employee wages if an employee has not met a certain threshold number of days worked or an amount of wages earned for services performed in the state. States have inconsistent, differing requirements (see APA's Guide to State Payroll Laws §3.1).
Mobile workforce issues
When an employee travels for business and performs work in a state other than the employee's usual work state, withholding requirements become even more complicated. Employees who work in multiple states are potentially subject to state income tax in every state to which they have traveled for business, even if they performed services in that state during only one day.
The APA is part of the Mobile Workforce Coalition, a group advocating for passage of federal legislation to establish a uniform threshold for state taxation of nonresident income. The legislation has been introduced a number of times since 2006.
In general, proposed legislation would establish a 30-day threshold, meaning an employee's wages for services performed in a state would not be subject to income taxation in that state until the employee is present and performing employment duties for more than 30 days during the calendar year. Employers (with nexus to the state) would not be required to withhold until the threshold has been met.
In addition to several proposed bills similar or identical to the Mobile Workforce Coalition's model legislation, a recently proposed COVID-19 relief package includes a provision that would establish a uniform 30-day threshold for state taxation of nonresident income. During the pandemic, the threshold would be extended to 90 days. Links to proposed federal legislation are provided below.
APA actively submits statements and urges lawmakers to vote for its passage. Links to statements and letters are under APA Government Relations Mobile Workforce Issues below.
- PayState Update, Issue 18, September 14, 2020
- PayState Update, Issue 17, August 31, 2020
- PayState Update, Issue 16, August 17, 2020
- Inside Washington, July 2020
- PayState Update, Issue 13, June 29, 2020
- PayState Update, Issue 9, May 4, 2020
- Payroll Currently, Issue 4, April 2020
- Capitol Hill Update: Mobile workforce. S. 604, the Mobile Workforce State Income Tax Simplification Act of 2019, would establish a 30-day threshold before a state could impose income tax on a nonresident employee's wages.
- Payroll Currently, Issue 3, March 2020
- Capitol Hill Update: Mobile workforce. H.R. 4796/H.R. 5674, the Mobile Workforce State Income Tax Simplification Act, would establish a 30-day threshold before a state could impose income tax on a nonresident employee's wages.
- PayState Update, Issue 24, December 23, 2019
- APA News, December 12, 2019
- PayState Update, Issue 18, September 16, 2019
- Inside Washington, May 2019
- APA News, April 26, 2019
- PayState Update, Issue 8, April 15, 2019
- August 27, 2020: Letter to the House and Senate in support of Section 403 of S. 4318, American Workers, Families, and Employers Assistance Act, and S. 3995, the Remote and Mobile Worker Relief Act of 2020.
- June 29, 2020: Letter to congressional leadership supporting S.3995, Remote and Mobile Worker Relief Act of 2020.
- June 29, 2020: Letter to U.S. Sens. Thune and Brown supporting S.3995, Remote and Mobile Worker Relief Act of 2020.
APA Education Links:
- H.R. 4796 – Mobile Workforce State Income Tax Simplification Act
- S. 604 – Mobile Workforce State Income Tax Simplification Act
- H.R. 5674 – Mobile Workforce State Income Tax Simplification Act
- S. 3995 – Remote and Mobile Worker Relief Act
- S. 4318 – American Workers, Families, and Employers Assistance Act