How can I file an extension for my North Dakota state taxes?

Extension of time to file
You may obtain an extension of time to file your North Dakota individual income tax return by obtaining either a federal extension or a North Dakota extension.

Federal Extension
If you obtain an extension of time to file your federal return, it will be recognized for North Dakota purposes. This includes the automatic extension allowed for being outside the U.S. and Puerto Rico on April 15. You do not have to file a separate state extension form, nor do you have to notify the Office of State Tax Commissioner that you have obtained a federal extension prior to filing your North Dakota return. Fill in the circle next to "Extension" on Form ND-EZ or Form ND-1, whichever applies.

North Dakota Extension
If you do not obtain a federal extension, but need additional time to file your North Dakota return, you may apply for a North Dakota extension by completing and filing Form 101. This is not an automatic extension you must have good cause to request a North Dakota extension. Form 101 must be postmarked on or before the due date of your return. You will be notified whether your extension request is approved or rejected. If approved, fill in the circle next to "Extension" on Form ND-EZ or Form ND-1, whichever applies.

Extension interest
If you obtain an extension and file your North Dakota return on or before the extended due date, and you pay any tax balance due with the return, no penalty will be charged. Interest on any tax due on the return will be charged at the rate of 12% per year from the original due date of your return to the earlier of the date you fi le your return or the extended due date.

Prepayment of tax due
If you are applying for an extension of time to file, you may prepay the tax that you expect to owe to avoid paying extension interest. To do so, submit your check or money order along with a completed Form ND-1EXT on or before April 15. Alternatively, you may submit your payment along with a letter containing the following:
- Your name.
- Your social security number.
- Your address and phone number.
- Statement that you are making  Form ND-1EXT payment (include the tax year payment is for).

If you do not file your return by its due date (including extensions), a penalty equal to 5% of the tax due or $5.00, whichever is greater, applies for the month the return was due, with an additional 5% of the tax due for each month (or fraction of a month) the return remains delinquent, not to exceed 25% of the tax due. In addition to any penalty, interest must be paid at the rate of 1% per month (or fraction of a month), except for the month in which the tax was due, on any tax due that remains unpaid after the return's due date (including extensions).