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New Hampshire Business State Tax Extension I C Corporations Filing Guide

Form BT-EXT | Payment Form and Application for 7-Month Extension of Time to File Business Tax Return  ·  C Corporations  ·  Business Filing Guide

Overview

New Hampshire C Corporations are subject to state corporate income tax requirements, administered by the New Hampshire Department of Revenue Administration. New Hampshire automatically grants an extension to file with no application or form submission required.

Original Filing Deadline

The original due date for the New Hampshire C Corporations return is April 15, 2026. File or remit full payment by this date to remain in good standing.

Extension Granted Automatically

New Hampshire automatically grants a filing extension for C Corporations. The extended filing deadline is October 15, 2026. No application or form submission is required to receive this extension.

Payment Is Still Due by Original Deadline

The extension applies to filing only—it is not an extension to pay taxes owed. Any outstanding tax liability must be paid by the original due date of April 15, 2026 to avoid penalties and interest. Use the New Hampshire | Online Tax Extension Payment to pay electronically. For mail-in payments, use Form BT-EXT | Payment Form and Application for 7-Month Extension of Time to File Business Tax Return and send to: New Hampshire Department of Revenue Administration P.O. Box 1265 Concord, NH 03302-1265

Late Filing and Payment Penalties

• Failure to File: N/A, because state does not tax general business corporation or pass-through income.
• Failure to Pay: N/A, because state does not tax general business corporation or pass-through income.

Best Practices

• Estimate and pay your New Hampshire business tax by April 15, 2026 to avoid interest and penalties.
• No extension form is required—New Hampshire grants the extension automatically.
• Use the state online payment portal for fast, convenient electronic payment.
• Set a reminder to file your completed New Hampshire C Corporations return by October 15, 2026.

Final Thoughts

• New Hampshire’s automatic extension simplifies the process—no paperwork required. Pay any balance due by April 15, 2026 and file your return by October 15, 2026.
• Quick Reference Table
• State Abbreviation
• NH
• State Name
• New Hampshire
• Business Entity Type
• C Corporations
• Extension Status
• Approved Automatically
• Return Due Date
• April 15, 2026
• Extended Due Date
• October 15, 2026
• Other Information
• New Hampshire grants you an automatic 6-month extension to file your business tax return. The extension is NOT an extension to pay any taxes you may have due. Tax payments are due by the original return due date.
• Online Payment
• New Hampshire | Online Tax Extension Payment
• Payment Voucher Form
• Form BT-EXT | Payment Form and Application for 7-Month Extension of Time to File Business Tax Return
• State Payment Agency
• New Hampshire Department of Revenue Administration
• Mailing Address with Payment
• New Hampshire Department of Revenue Administration P.O. Box 1265 Concord, NH 03302-1265
• Failure to File Penalties
• N/A, because state does not tax general business corporation or pass-through income.
• Failure to Pay Penalties
• N/A, because state does not tax general business corporation or pass-through income.

Working with a Tax Professional

Business tax returns are complex—a licensed CPA or Enrolled Agent can maximize deductions, ensure accurate calculations, and handle filing on your behalf. Here's how working with a TaxPro typically goes:

1. 1Get matched with a verified U.S.-based CPA or Enrolled Agent
2. 2Upload your business documents via secure drag-and-drop
3. 3Review and approve your return with upfront, transparent fees
4. 4Your TaxPro files your New Hampshire return by October 15, 2026

Quick Reference Table

State Abbreviation	NH
State Name	New Hampshire
Business Entity Type	C Corporations
Extension Status	Approved Automatically
Return Due Date	April 15, 2026
Extended Due Date	October 15, 2026
Other Information	New Hampshire grants you an automatic 6-month extension to file your business tax return. The extension is NOT an extension to pay any taxes you may have due. Tax payments are due by the original return due date.
Online Payment	New Hampshire | Online Tax Extension Payment
Payment Voucher Form	Form BT-EXT | Payment Form and Application for 7-Month Extension of Time to File Business Tax Return
State Payment Agency	New Hampshire Department of Revenue Administration
Mailing Address with Payment	New Hampshire Department of Revenue Administration P.O. Box 1265 Concord, NH 03302-1265
Failure to File Penalties	N/A, because state does not tax general business corporation or pass-through income.
Failure to Pay Penalties	N/A, because state does not tax general business corporation or pass-through income.