How to File Form NC-40: North Carolina Individual Estimated Income Tax

To fill out Form NC-40, use the worksheet on page two of the form to calculate your expected North Carolina tax, divide the result by four, and enter that quarterly amount on the voucher along with your name, Social Security number, and the tax year. You then submit the voucher and payment to the Department of Revenue online or by mail. The form itself is short; the arithmetic behind it is where the work lives.

Do You Actually Need to File NC-40?

You owe North Carolina estimated tax if you expect to owe $1,000 or more in state income tax after subtracting your withholding and credits.¹ That typically hits people with self-employment income, business profits, investment gains, rental income, or anything else that doesn’t have North Carolina tax withheld at the source.

One exemption: if you had no North Carolina tax liability at all for the prior year, you’re off the hook for the current year regardless of what you earn.²

Calculate Your Quarterly Amount

The NC-40 worksheet on page two walks through the full calculation. The flow:³

Line 1: Enter your expected federal adjusted gross income for the year.
Lines 2–4: Add any North Carolina additions to federal AGI, then subtract any North Carolina deductions. The Form D-400 instructions spell out which items apply.
Line 5: Enter the child deduction amount if you qualify. The current amount is listed on the Department of Revenue’s website.
Line 6: Enter your standard or itemized deduction. For tax year 2025, the North Carolina standard deduction is $12,750 for single filers and $25,500 for married filing jointly or qualifying surviving spouse. These are not the same as the federal figures.⁴
Line 7: Subtract total deductions from the adjusted figure on Line 3 to get taxable income.
Line 8: Multiply taxable income by the applicable flat rate. The rate was 4.50% for 2024 and has been scheduled to decline under enacted legislation, so check the NCDOR tax rate schedule for your tax year.⁵
Lines 9–10: Subtract expected North Carolina withholding and any tax credits.
Line 11: If the result is $1,000 or more, divide by four. That’s the amount you’ll enter on each voucher.

If you had an overpayment on last year’s D-400 and elected to apply it to this year’s estimated tax, you can credit all or part of it against any installment. You only need to send a voucher for installments where you’re actually making a payment.³

Fill In the Voucher

Once the worksheet is done, the voucher itself takes a minute:³

Enter your full legal name and Social Security number. If you plan to file a joint return, include your spouse’s name and SSN too.
Enter the four-digit tax year the payment applies to. Fiscal year filers enter their beginning and ending dates in the boxes provided.
Enter one-fourth of the amount from Line 11 of the worksheet in the payment box. Dollar figure only, no dollar signs or extra text.

If your income shifts partway through the year, redo the worksheet and adjust the amount on your remaining vouchers. You aren’t locked into the same number every quarter.

Submit and Pay

Online

The Department of Revenue’s online system at eservices.dor.nc.gov lets you complete and submit the voucher electronically and pay by bank draft (ACH) or credit/debit card.⁶ Card payments carry a convenience fee of $2.00 per $100.00 of the payment amount.⁷ On a $3,000 payment that’s $60 in fees. Bank draft avoids the fee, which matters on larger amounts.

By Mail

Print the completed voucher and mail it with a check or money order to:¹

North Carolina Department of Revenue
P.O. Box 25000
Raleigh, NC 27640-0630

Make the check or money order payable to the N.C. Department of Revenue in U.S. currency. Don’t send cash. On the memo line, write the last four digits of your SSN, the tax year, and “NC-40.” Your name, address, and daytime phone number should appear on the check itself.³ A postmark on or before the deadline counts as timely.

Quarterly Deadlines

Calendar-year filers follow four due dates:¹

1st installment: April 15
2nd installment: June 15
3rd installment: September 15
4th installment: January 15 of the following year

When a due date lands on a weekend or legal holiday, it rolls to the next business day.⁸

Avoid Interest Charges

North Carolina charges interest, not a flat penalty, when your estimated payments fall short.² You stay in the clear if your combined payments, withholding, and credits cover at least the lesser of:

90 percent of the tax shown on your current-year return, or
100 percent of the tax shown on your prior-year return, provided that year was a full 12-month period and you filed a return.²

Matching 100 percent of last year’s tax is the easier target if your income swings around. North Carolina doesn’t bump this to 110 percent for high earners the way the federal rules do.

Each installment is evaluated on its own. If you underpay in April and overpay in September to catch up, you’ll still owe interest on the April shortfall for the months it sat unpaid.⁹ This catches people off guard; catching up later doesn’t erase what already accrued.

There’s one escape valve for the final installment. If you file your full D-400 return and pay the entire balance by January 31, no interest is charged on the fourth installment even if it was short.² That gives you roughly two weeks after January 15 to settle up on that last payment.

Farmers and Fishermen Use a Different Schedule

If at least two-thirds of your gross income comes from farming or fishing (oyster farming counts), you make one estimated payment due January 15 of the following year instead of four quarterly installments.² The required amount is the lesser of 66⅔ percent of your current-year tax or 100 percent of your prior-year tax. You can also skip estimated payments entirely by filing your return and paying the full balance by March 1. The two-thirds test can be met using either current-year or prior-year gross income, whichever qualifies you.

1
North Carolina Department of Revenue. Estimated Income Tax
2
North Carolina General Assembly. North Carolina Code 105-163.15 – Failure by Individual to Pay Estimated Income Tax; Interest
3
North Carolina Department of Revenue. NC-40 Individual Estimated Income Tax Instructions
4
North Carolina Department of Revenue. North Carolina Standard Deduction or North Carolina Itemized Deductions
5
North Carolina Department of Revenue. Tax Rate Schedules
6
North Carolina Department of Revenue. NC-40 Individual Estimated Income Tax
7
North Carolina Department of Revenue. Payment FAQs
8
Internal Revenue Service. When to File
9
North Carolina Department of Revenue. Interest Overview