Before you start

An SSN or ITIN
Form W-4 with your employer for federal withholding
North Carolina Form NC-4 for state withholding
Records of foreign income and foreign financial accounts

Step-by-step

1
Complete the W-4 and the NC-4 on day one
North Carolina has its own withholding certificate rather than deriving everything from the federal form, and the two can drift apart in a two-income household. Getting either wrong is the most common cause of an April surprise.
Via employerWho: YouFirst week of employment
2
Determine your US tax residency
The substantial presence test counts weighted days across three years to decide whether the US taxes your worldwide income or only US-source income. Certain students and scholars are exempt from counting days for a period. Your visa category does not settle this.
OnlineWho: You
3
Check for an applicable tax treaty and how NC treats it
The US has income tax treaties with around 70 countries. North Carolina begins from federal adjusted gross income, so a federal treaty exclusion generally flows through to the state return — unlike California, which ignores treaties entirely. That is a real advantage for researchers and postdocs choosing between states.
OnlineWho: You
4
File federal and North Carolina returns by 15 April
The tax year is the calendar year. Because North Carolina applies one flat rate to a federal starting point with a generous standard deduction, the state return is among the quickest in the country to prepare.
OnlineWho: YouBy 15 April annually
5
File an FBAR if foreign accounts exceed $10,000
Aggregate foreign financial account balances above $10,000 at any point in the year trigger a FinCEN filing, separate from your tax return. An ordinary current account at home is often enough to cross it.
OnlineWho: You
6
If you buy, watch the four-year revaluation cycle
Wake County reassesses property values on a four-year cycle rather than annually, so a revaluation year produces a step change in the bill rather than a gradual drift. Budget for the jump, and know that you have a limited window to appeal a new valuation.
OnlineWho: You

Documents you’ll need

Form W-2 from each employer, issued by 31 January
Form 1099s for freelance, interest and investment income
Passport and travel history for the substantial presence day count
Foreign account statements for FBAR reporting
Wake County property tax notice and vehicle Tag & Tax bill, if applicable

Things most newcomers don’t know

The flat rate is scheduled to fall twice more, and the triggers have been met so far.

North Carolina's rate is 3.99% for 2026 and drops by statute to 3.49% for 2027 and 2.99% for 2028, conditional on revenue triggers. Consensus forecasts have projected those triggers being met. For anyone modelling a multi-year stay, that is a materially different picture from a static rate — and it is the opposite direction of travel from most states in this app.

Source: NC Department of Revenue — tax rate schedules

There is no local income tax anywhere in North Carolina.

Portland stacks Metro and Multnomah County taxes on top of Oregon's; New York City levies its own; Denver charges a head tax. North Carolina prohibits local income taxes outright, so your state rate is the whole state-and-local income tax story. Combined with a sub-1% property tax in Wake County, the total local burden here is genuinely lower than the headline comparison with Texas suggests.

Source: NC Department of Revenue

North Carolina follows federal treaty exclusions; California does not.

Because the NC return starts from federal adjusted gross income, income excluded under a US tax treaty generally does not reappear at state level. California explicitly does not conform and taxes that income anyway. For a postdoc, visiting researcher or graduate student weighing offers between states, that difference can be worth thousands a year and it is almost never mentioned in a recruitment conversation.

Source: NC Department of Revenue

Vehicle property tax arrives with your registration, in one bill.

North Carolina collects an annual county property tax on vehicles at the same time as the registration renewal, under the 'Tag & Tax Together' programme. The amount scales with the vehicle's assessed value, so a newer car costs meaningfully more each year. Newcomers receive a renewal notice several times larger than expected and assume it is a billing error.

Source: NCDMV — Tag & Tax Together

Common mistakes to avoid

Assuming the flat rate is fixed, when it is on a statutory downward schedule.
Filing only the federal return and forgetting North Carolina has its own NC-4 withholding form.
Budgeting from last year's property tax bill in a Wake County revaluation year.
Being surprised by the combined vehicle Tag & Tax renewal bill.
Believing a filing extension also extends the payment deadline — it does not.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.