Here’s what HIVE AI had to say about “When are 2025 business tax return deadlines?”:

2025 Federal Business Return Deadlines

Partnerships (Form 1065) and S Corporations (Form 1120-S)

• Calendar-year filers (tax year ending Dec 31, 2024): due March 17, 2025 (March 15 falls on a Saturday)
• Fiscal-year filers: due the 15th day of the 3rd month after year-end
• Extension: automatic 6 months by filing Form 7004 (does not extend time to pay) 1 2

C Corporations (Form 1120)

• Calendar-year filers (tax year ending Dec 31, 2024): due April 15, 2025
• Fiscal-year filers: due the 15th day of the 4th month after year-end (June 30 year-ends have special extension rules)
• Extension: up to 6 months with Form 7004; special temporary rules apply to certain pre-2026 year-ends (5 months for C corps with Dec 31 year-ends beginning before Jan 1, 2026; 7 months for June 30 year-ends beginning before Jan 1, 2026) 3 4

Foreign Corporations (Form 1120-F)

• Due the 15th day of the 6th month after the end of the tax period (when Box D(3) not checked); weekends/holidays observed. For example, a September 30, 2025 year-end is due March 16, 2026, with a 6-month extension to September 15, 2026; June 30 fiscal year typically has a 7-month extension. 5 6

Information Return and Statement Highlights (commonly affecting businesses)

• ACA Forms 1094-B/1095-B for 2024 coverage: file by Feb 28, 2025 (paper) or Mar 31, 2025 (electronic); 30-day automatic filing extension available via Form 8809 7
• Annual recipient statements (certain 1099s for payments made in 2024): generally due to recipients by Jan 31, 2025; paper/e-file deadlines vary by form; see IRS Tax Calendar for specifics and legal holidays that can shift due dates 8 9

Estimated Tax (business owners/corporations)

• Individuals (incl. pass-through owners) often pay estimated tax on 4/15/2025, 6/17/2025, 9/16/2025, and 1/15/2026; April 15 is confirmed for Q1 2025 by IRS notice. Check entity-specific rules for corporate estimated tax. 10

Disaster and Special Relief That May Change Your Deadline

• The IRS periodically postpones filing and payment deadlines for taxpayers in disaster areas. For example, certain 2024–2025 acts have been postponed to specific dates (e.g., Helene relief to May 1, 2025; Missouri events to Nov 3, 2025). Always verify current relief for your location and period. 11 12

Penalties note

• Late-file penalty for certain corporation returns required to be filed in 2025 and filed more than 60 days late: the lesser of tax due or $510 minimum; late-payment penalty generally 0.5% per month up to 25% (reasonable cause exceptions apply) 13

If you share your entity type, year-end, and state, I can give you the exact 2025 due dates and extension dates that apply to you (including any current disaster relief).

Sources

1 – IRC § 6072(b) 📄 Summarize
2 – Treasury Regulation 1.6037-1 📄 Summarize
3 – T.D. 9821 📄 Summarize
4 – IRC § 6081(b) 📄 Summarize
5 – IRS IRM 3.11.16 Corporate Income Tax Returns 📄 Summarize
6 – IRS.gov – Instructions for Form 1120-F (2024) 📄 Summarize
7 – IRS.gov – Instructions for Forms 1094-B and 1095-B (2024) 📄 Summarize
8 – IRS – Publication 509 Tax Calendars 📄 Summarize
9 – IRS.gov – Tax Calendar 📄 Summarize
10 – IRS Newsroom – IR-2025-45 📄 Summarize
11 – IRS Newsroom – IR-2024-253 📄 Summarize
12 – IRS Newsroom – 📄 Summarize
13 – IRS.gov – Instructions for Form 1120 (2024) 📄 Summarize

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