Five years ago, most of your team probably worked in one or two states. Now you've got an engineer in Texas, a sales rep in New York, a customer success lead who moved to Florida and didn't tell anyone right away. Remote work was a gift for hiring. For payroll, it created a quiet pile of compliance questions that someone has to answer correctly, every pay period, in every state where someone lives or works.
Multi-state payroll is where a lot of growing companies get tripped up, and it's rarely because anyone was careless. The rules are genuinely complicated. Where do you register? Which state's tax applies, the one where the person lives or the one where they work? What about the city tax nobody mentioned? Get it wrong and you're looking at penalties, amended filings, and frustrated employees who under- or over-withheld all year.
The good news is that ADP Workforce Now handles multi-state payroll well once it's set up right. The catch is in those last three words. Below is a practical guide to staying compliant when your team works everywhere, the common mistakes we see, and how to keep it clean. This is general guidance; confirm your specific situation with a licensed tax advisor.
Before you can withhold and remit taxes in a state, you generally have to be registered there as an employer. This usually means registering with the state's tax agency and its unemployment agency, and getting the account numbers that let you file and pay.
Here's the trap: having one employee in a state often triggers a registration obligation, even if that employee is your only presence there. The moment someone starts working from a new state, you may have created what's called nexus, an obligation to register and withhold. Companies frequently discover they've owed registrations for months because an employee quietly relocated.
The fix is process, not heroics. Before anyone's first paycheck in a new state, confirm whether you need to register there and get the account numbers in hand. ADP Workforce Now needs those numbers to file and remit correctly, so registration is step one, not an afterthought.
This is the question that confuses almost everyone. When an employee lives in one state and works in another, which state gets the income tax?
The general rule is that income tax is owed to the state where the work is performed, and the employee's home state may also tax the same income because it taxes residents on all income. That can mean two states have a claim. Most states resolve the double-tax problem by giving residents a credit for taxes paid to another state, but the withholding still has to be set up correctly so the right amounts go to the right places.
For a fully remote employee, the work state and residence state are usually the same: wherever they sit to do the job. For someone who lives near a border and commutes, or who travels between locations, it gets more involved. The key is to know, for each employee, where they live and where they actually perform the work, and to set the system up to match. Guessing is how you end up with a mess at year-end.
Some neighboring states have reciprocity agreements with each other. These are deals that simplify the cross-border situation: an employee who lives in one state and works in another only pays income tax to their home state, and the employer withholds for the home state instead of the work state.
When a reciprocity agreement applies, the employee typically files a form with the employer to claim it. That form is what tells you to withhold for the residence state rather than the work state. Miss the form and you withhold for the wrong state, which means the employee pays into a state they don't owe and has to sort it out at tax time.
Reciprocity only exists between certain state pairs, and the rules vary. Don't assume it applies just because two states are next to each other. Check the specific pair, get the right form on file, and set the withholding accordingly. And keep in mind that an agreement covering one direction may not work the same in reverse, so confirm the rule for the exact living-and-working combination in front of you rather than applying a blanket assumption.
State income tax is only part of the picture. A number of cities, counties, and school districts levy their own income or wage taxes, and these are easy to miss because they don't show up at the state level.
Local taxes can depend on where the employee lives, where they work, or both, and the rules differ from place to place. An employee who moves to a new town within the same state can pick up a local tax obligation that the state-level setup never flagged. These smaller taxes cause an outsized share of corrections because they're so easy to overlook.
The habit that protects you: whenever an employee's home or work location changes, check not just the state but the local jurisdictions too. ADP Workforce Now can handle local taxes when they're set up, but the system only knows what you tell it about where the person is.
A few states are known for dense local taxation, where a single move across a city or school district line changes what's owed. If you have employees in those areas, treat local tax as a standing item rather than a one-time setup. The amounts are often small per paycheck, which is exactly why they slip through. They're easy to ignore until a year of small errors adds up to a correction nobody wants to explain.
Once you know the facts for each employee, the work is making the system match them. In ADP Workforce Now, each employee's tax setup reflects their work location and residence location, and the system applies the right state and local taxes based on that.
The single most important data point is accurate, current location information for every employee. Their tax withholding flows from their addresses and assigned work location. If an employee moves and their record isn't updated, the system keeps withholding for the old location, and the error compounds with every paycheck until someone catches it.
So the discipline is twofold. First, make sure new employees are set up in the correct jurisdictions from day one. Second, build a process so that when someone moves, their record gets updated promptly and the registration question gets asked. The system does the heavy lifting on calculation. Your job is keeping the inputs honest.
A handful of mistakes show up again and again.
An employee moves states and tells HR weeks later, so withholding lags behind reality. The company never registered in a new work state, so taxes were withheld but couldn't be remitted correctly. A reciprocity form was never collected, so withholding went to the wrong state all year. Local taxes were missed because everyone focused on the state level. And the classic: an employee record shows the office address even though the person has worked from another state for a year.
Almost every one of these traces back to the same root, a gap between where the employee actually is and what the system thinks. Close that gap with process and most multi-state problems disappear.
A client with about 250 employees grew from two states to eleven over two years of remote hiring. They came to us after spotting that three employees had been set up with the company's headquarters location instead of their actual work states. Those employees had been under-withheld for their home states for most of the year, and the company hadn't registered in two of the states where people were now working.
We worked through the full roster, confirmed each employee's real work and residence locations, and corrected the records in ADP Workforce Now. We flagged the two states needing registration so the company could get the accounts in place, and we identified two employees who qualified for a reciprocity agreement and got the right forms on file. Then we set up a simple change-of-address process so future moves would trigger a tax review automatically.
The numbers are rounded and illustrative, but the shape is typical: a handful of misconfigured records, a couple of missing registrations, and a process gap that let it happen. Fixed at the root, with a process to keep it fixed, the recurring corrections stopped.
"An employee just moved to a new state. What do we actually have to do?"
Update their work and residence location in the system, check whether you need to register as an employer in the new state, and confirm which local taxes now apply. If the move is between reciprocity states, get the right form on file. Do this before the next payroll if you can, so withholding matches reality from the start. Confirm the specifics with your tax advisor.
"Do we really have to register in a state for just one remote employee?"
Often, yes. A single employee working in a state can create an obligation to register and withhold there. The exact triggers vary by state, so confirm with a licensed advisor, but don't assume one person is too small to matter. That assumption is behind a lot of surprise notices.
"Which state's tax applies if someone lives and works in different states?"
The general rule is the work state taxes income earned there, and the residence state may tax it too, usually with a credit to avoid true double taxation. Reciprocity agreements can change this for certain state pairs. The right setup depends on the specific states, so verify each case rather than applying one rule everywhere.
The companies that handle multi-state payroll well aren't smarter about tax law. They have better process. Build these habits and most of the risk goes away.
Make location part of onboarding and offboarding, so every employee's work and residence state is confirmed and entered correctly from the start. Create a change-of-address process that triggers a tax review every time, not just a record update. Keep a running list of every state and locality where you have employees, and revisit your registrations against it. And review the whole roster at least once a year to catch anyone whose situation drifted. Good looks like a clean roster where every employee's setup matches where they actually are, and no surprises at year-end.
Multi-state setup in ADP Workforce Now is detailed work, and the cost of getting it wrong is real. Ignite HCM is staffed Only by former ADP service professionals who have configured multi-state payroll many times over. We work with ADP exclusively, so this is exactly the kind of work we know cold.
You get a dedicated consultant who learns your roster and your situation, not a queue. No tickets, no hold queues — a dedicated consultant on the line. Your people need to get paid right, in every state they live and work. We make that happen.
Got employees scattered across states and a nagging feeling something's off? REQUEST A CONSULTATION (ignitehcm.com/solutions/compliance).
ADP and the ADP logo are registered trademarks of ADP, Inc. This article is general guidance only and not tax, legal, or compliance advice. State and local tax rules change and vary by jurisdiction; confirm your specific situation with a licensed tax advisor.
