The N.H.-Mass. tax fight could have implications that go far beyond our borders

Tens of thousands of New Hampshire residents could be affected, as could millions of other telecommuters, depending on the Supreme Court’s decision

Governor Chris Sununu applauded the Executive Council after swearing them in during his inauguration ceremony in Concord, N.H., on Jan. 7. Sununu is leading litigation to overturn a taxation rule in Massachusetts that affects thousands of his constituents.David Lane/Associated Press

At first glance, the border battle between Massachusetts and New Hampshire over income taxes might seem like a mere squabble between two neighbors.

But the fallout could be felt nationwide once the dust finally settles because of the rising acceptance of remote work, and the trend’s implications for state tax policies.

At issue is whether the Massachusetts Department of Revenue can continue to collect income taxes from out-of-state workers stuck at home since last March because of COVID-19. The DOR says yes, it’s only temporary. Officials in income-tax-free New Hampshire say no way.

A frustrated Governor Chris Sununu had enough in October, after the weeks turned into months. That’s when he sued his southern neighbor in the US Supreme Court, declaring the Massachusetts telecommuter tax unconstitutional. Sununu argued that the Baker administration was stomping on the “New Hampshire Advantage” — that is, the allure to live or work in a state without a broad-based income tax.

Many observers on both sides of the state line had been hoping we would hear by now whether the Supreme Court would take up the case. No such luck there.

Rather than agreeing with New Hampshire’s request to referee the dispute, the Supreme Court on Monday instead sought guidance from the acting solicitor general to get the Biden administration’s views. It wasn’t the outright denial that the Massachusetts DOR had sought. And it certainly signals an interest by the Supremes. But it’s still not a sure thing that they will intervene.

The Baker administration says it’s simply maintaining a status quo, by treating out-of-state workers like they were before the pandemic hit, when they were taxed for each day they worked in Massachusetts. The administration had said it would jettison this rule by Dec. 31. However, as New Year’s Eve approached with no end of the pandemic in sight, the DOR extended it. This time, the Massachusetts agency offered no specific end date — only 90 days after the Baker administration lifts the state of emergency. The move confirmed the suspicions in New Hampshire that relief wouldn’t be coming anytime soon.

How much money is at stake for Massachusetts? The DOR says it doesn’t have any official data to share.

But we do have a general idea of how many people could be affected. In the original motion with the Supreme Court, the New Hampshire attorney general’s office said more than 103,000 residents worked for companies based in Massachusetts in 2017. An older estimate showed about 84,000 commuters regularly driving over the state line to work in Massachusetts.

Jared Walczak, a state policy expert with the nonprofit Tax Foundation, said the Supreme Court could choose a narrow focus — perhaps deciding on just how long Massachusetts can continue to cling to the prepandemic taxation system while most white-collar workers are home.

Walczak said it’s more likely the court will take up the broader issue of whether state officials can impose income taxes on people who neither live nor work within their borders. Before the pandemic, six states had so-called “convenience of the employer” rules to collect income taxes from people who worked and lived out of state, but with employment linked to a local office. Those include Delaware, Pennsylvania, New York, Nebraska, and Arkansas. Connecticut also has one of these rules, but it only kicks in for people who work for a Connecticut company and live in a state where such a rule is in place. (Take that, New York!)

As Walczak likes to say, these convenience rules are anything but convenient for taxpayers. If the Supreme Court eventually decides in New Hampshire’s favor, the ruling could potentially upend all of them.

That would be the hope of officials in four states — Connecticut, New Jersey, Iowa, and Hawaii — who sided with New Hampshire in a brief filed with the court. There are no income tax dollars at stake for New Hampshire. But billions of dollars are on the line for other states, their brief says, mainly because of tax credits offered to avoid double taxation.

If the Supremes side with Massachusetts, other state tax commissioners could be emboldened to adopt convenience rules of their own. The revenue departments most likely to join the fun are those in states with large corporate bases, and significant numbers of employees who continue to work remotely after the pandemic ends.

Richard Jones, a Boston tax lawyer at Sullivan & Worcester, said he understands the Department of Revenue’s point of view: The agency’s main stated goal is to minimize the disruption that the pandemic could cause for employers, especially those with workforces now scattered to far-flung places. The longer the Massachusetts rule remains in place, he said, the tougher it will be to make that case.

Jones said it could take a few months for the solicitor general to respond to the court, and even longer before the court decides to even take up the case. If it does, the court’s deliberations might even outlast the pandemic.

Walczak said convenience rules have been challenged before in New York courts, for example, by nonresidents weary of paying New York taxes. Those were unsuccessful.

This time could be quite different. The stakes are much higher. We are entering a new world order for employers, and for employees who want the flexibility to work at home after COVID-19 is a bad memory. Convenience rules could potentially affect millions of existing and prospective telecommuters, and the future of the workplace just might hang in the balance.