SEC Filing Deadlines 2026: Complete Calendar by Filer Type

If you're building or validating your 2026 SEC compliance calendar, the published PDF guides from law firms cover the basics for December 31 fiscal year-end companies. This guide goes further: exact dates for all filer categories, the deadlines buried inside the deadlines (financial statement staleness, cybersecurity 8-K, Section 16), the 2026 holiday roll-forwards that shift actual due dates, and the compliance mistakes that turn a manageable situation into a 12-month loss of S-3 eligibility.

Key takeaway: SEC filing deadlines are tiered by filer category, adjusted for 2026 federal holidays, and layered with secondary clocks, staleness, 8-K trigger events, Form 12b-25, that most calendar tools don't show. Miss any one of them and the consequences compound quickly.

What Are the 2026 SEC Filing Deadlines by Filer Category?

Your filer category determines every core deadline. Under Rule 13a-1, the three domestic issuer categories are:

• Large Accelerated Filer (LAF): public float of $700 million or more as of the last business day of the most recently completed second fiscal quarter (June 30 for calendar-year companies). 10-K due within 60 calendar days of fiscal year-end.
• Accelerated Filer (AF): public float of $75 million to $699 million. 10-K due within 75 calendar days.
• Non-Accelerated Filer (NAF) / Smaller Reporting Company (SRC): below the AF threshold. 10-K due within 90 calendar days.

Filer category is measured on the last business day of Q2 each year under Rule 12b-2. A company's June 30, 2025 float determines its category for all 2026 periodic filings. Misclassifying, say, treating yourself as a NAF when your float crossed $75 million, means you filed your 10-K 15 days late without knowing it.

10-K Deadlines for December 31, 2025 Fiscal Year-End

Presidents' Day falls on February 16, 2026, but none of the standard December 31 FY-end 10-K deadlines land on a weekend or that holiday, so no roll-forward applies to the dates above.

10-Q Deadlines for Calendar-Year Filers in 2026

Under Rule 13a-13, LAFs and AFs have 40 calendar days from quarter-end; NAFs have 45 days.

Note: Q3 NAF deadline falls on November 14 (45 days) but Veterans Day is November 11 and is not a weekend, so confirm whether November 14 is a Saturday in 2026, it falls on a Saturday, rolling the NAF deadline to Monday, November 16, 2026.

10-K and 10-Q Deadlines for Non-December Fiscal Year-Ends

Most published calendars stop at December 31. If your fiscal year ends March 31, June 30, or September 30, apply the same day-count rules to your own year-end date, then roll forward if the result lands on a weekend or 2026 federal holiday.

For June 30 LAFs, the 60th day lands on a Saturday, so the actual deadline is Monday, August 31, 2026. Always run the roll-forward calculation yourself, vendor tools carry disclaimers that accuracy cannot be guaranteed and professional counsel should be sought.

2026 Federal Holidays That Affect Filing Deadlines

When a deadline falls on a weekend or federal holiday, it rolls to the next business day. The 2026 federal holidays relevant to SEC filers are:

• New Year's Day: January 1
• Martin Luther King Jr. Day: January 19
• Presidents' Day: February 16
• Memorial Day: May 25
• Juneteenth: June 19
• Independence Day: July 3 (observed, as July 4 falls on a Saturday)
• Labor Day: September 7
• Columbus Day: October 12
• Veterans Day: November 11
• Thanksgiving: November 26
• Christmas Day: December 25

EDGAR is closed on each of these dates and accepts no filings. Build these into your internal calendar now, not the week before a deadline.

EDGAR Submission Hours and the 5:30 p.m. Cutoff Trap

EDGAR accepts filings from 6:00 a.m. to 10:00 p.m. Eastern Time on business days. But the cutoff that actually matters for dating purposes is 5:30 p.m. ET.

Per the EDGAR FAQ: filings submitted after 5:30 p.m. ET receive the next business day's filing date. If your 10-K is due March 2 and you submit at 6:00 p.m. on March 2, EDGAR timestamps it March 3. That is a late filing, regardless of when the system accepted the transmission.

The one exception: Section 16 filings (Forms 3, 4, and 5) are not subject to the 5:30 p.m. cutoff. A Form 4 submitted at 9:45 p.m. still receives that day's date. Every other form type follows the 5:30 p.m. rule.

Practical implication: treat 5:00 p.m. ET as your internal hard stop on any deadline day. The 90 minutes between 5:00 p.m. and the EDGAR close exist for technical troubleshooting, not for finishing the document.

How the NT 10-K and NT 10-Q Extension Works

Form 12b-25 (NT 10-K or NT 10-Q) buys time, but it has strict mechanics of its own. Under Rule 12b-25:

• An NT 10-K grants 15 additional calendar days beyond the original 10-K deadline.
• An NT 10-Q grants 5 additional calendar days beyond the original 10-Q deadline.
• The Form 12b-25 itself must be filed within one business day (24 hours) of the original deadline. Miss that window and the extension is unavailable.

For a December 31, 2025 LAF, the original 10-K deadline is March 2, 2026. The NT 10-K must be filed by March 3, 2026, and the extended deadline becomes March 17, 2026.

Two things the extension does not do:

1. It does not guarantee SEC acceptance. The SEC can still deem the filing late if the stated reason for the delay is inadequate.
2. It does not preserve S-3 eligibility automatically. A company that ultimately files late, even after using the NT, loses Form S-3 access for 12 months from the date of the late filing.

Key takeaway: The NT 10-K is a tool for genuine operational delays, not a routine buffer. Using it and then missing the extended deadline is worse than missing the original, because it signals a systemic problem to SEC staff.

Form 13F Deadlines for Investment Managers in 2026

Institutional investment managers with $100 million or more in Section 13(f) securities must file Form 13F within 45 calendar days of each calendar quarter-end, per Rule 13f-1.

The Q4 2025 deadline of February 14 coincides with Form 5 (annual Section 16 filing) for December 31 fiscal year-end companies. Controllers and compliance teams with both obligations should plan accordingly.

Section 16 Reporting Deadlines in 2026

For officers, directors, and 10%+ shareholders, Rule 16a-3 sets three separate clocks:

• Form 3 (initial statement of beneficial ownership): due within 10 days of becoming a reporting person.
• Form 4 (changes in beneficial ownership): due within two business days of the transaction.
• Form 5 (annual statement): due within 45 days of the company's fiscal year-end. For a December 31, 2025 FY-end, the deadline is February 14, 2026.

For more on Form 3 mechanics and the 2026 NDAA changes for foreign private issuers, see SEC Form 3 Filing Requirements: 2026 Practitioner Walkthrough and the side-by-side comparison in Form 3 vs Form 4 vs Form 5: 2026 SEC Insider Reporting Comparison.

Remember: Section 16 filings submitted after 5:30 p.m. ET still receive the same day's date. That exception applies only to Forms 3, 4, and 5.

Form 8-K Deadlines: The Cybersecurity Clock Is Different

Most Form 8-K items require filing within four business days of the triggering event. The 2023 cybersecurity disclosure rules (SEC Release No. 33-11216, effective December 18, 2023) added a nuance that trips up compliance teams.

Under new Item 1.05, a material cybersecurity incident must be disclosed within four business days of the company determining the incident is material, not four days after discovery, and not four days after containment. The materiality determination is the clock-start.

This matters because a company may discover an incident on Monday, spend two weeks investigating, determine materiality on a Friday, and then have only four business days to file. The SEC has been clear that delayed materiality determinations will be scrutinized. Item 1.05 also requires annual disclosure of cybersecurity risk management, strategy, and governance in the 10-K (new Item 1C), which is now a standard checklist item for all domestic issuers.

For a full breakdown of the cybersecurity disclosure mechanics and what changed in 2026, see SEC in 2026: What Changed, Effective Dates, and What to Do Now.

Financial Statement Staleness: The Deadline Inside Capital Markets Transactions

This is the deadline layer that PDF calendars almost never show, and it catches companies mid-deal.

Under Reg S-X Rule 3-12, financial statements included in a registration statement (S-1, S-3, S-11, or any prospectus supplement) must not be older than 135 days at the time the registration statement becomes effective.

For a company planning a follow-on offering in Q2 2026 using December 31, 2025 audited financials, the 135-day clock runs from December 31, 2025. That means the registration statement must go effective by May 15, 2026, or the company must update the financials with Q1 2026 interim statements. If Q1 financials aren't ready, the offering stalls.

For companies doing live S-3 shelf takedowns, the staleness clock runs continuously. A company that files a prospectus supplement in August 2026 using June 30, 2026 quarter-end financials has until November 12, 2026 before those statements go stale. Miss it and the offering cannot proceed without updated financials.

The S-3 eligibility rules and the interaction between periodic reporting compliance and shelf access are covered in detail in S-3 Eligibility and Periodic Reporting Requirements: 2026 Practitioner Walkthrough.

Other 2026 Deadlines on the Compliance Checklist

Proxy Statement (DEF 14A)

Under Rule 14a-16, the proxy statement must be filed with the SEC and sent to shareholders at least 40 calendar days before the annual meeting date. For a June 2026 annual meeting, the DEF 14A must be filed by late April 2026. Annual meeting scheduling and proxy mailing logistics need to be planned backward from that date, not forward from the close of the fiscal year.

Form 11-K (Employee Benefit Plans)

Companies with ERISA-covered plans that file Form 11-K must do so within 180 days of the plan's fiscal year-end. For a December 31, 2025 plan year-end, the 2026 deadline is June 29, 2026. Plans with a non-December 31 fiscal year-end get 270 days.

Rule 10b5-1 Insider Trading Plan Disclosures

Since the SEC's 2023 amendments to Rule 10b5-1 (Release No. 34-96492), companies must disclose in each Form 10-Q and 10-K any adoption, modification, or termination of a Rule 10b5-1 trading plan by an officer or director during the quarter. This is now a standing item on every quarterly and annual reporting checklist.

Climate Disclosure: Still Stayed in 2026

The SEC's climate disclosure rules (Release No. 33-11275, adopted March 2024) remain subject to a voluntary stay pending litigation as of mid-2026. Companies are not yet required to comply with the new climate disclosure requirements in their 2026 periodic filings. Existing Reg S-K obligations still apply. For what your 10-K must include right now, see Climate Risk Disclosure in the 10-K: 2026 Practitioner Walkthrough.

What Happens If You Miss an SEC Filing Deadline?

The consequences stack, and they move fast.

S-3 eligibility loss. A company that files a required annual or quarterly report late loses the ability to use Form S-3 for 12 months from the date of the late filing. For companies with active shelf registrations or capital markets plans, this is the most immediately painful consequence. See S-3 Eligibility and Periodic Reporting Requirements: 2026 Practitioner Walkthrough for the full eligibility analysis.

Exchange deficiency notices. Nasdaq Rule 5250(c)(1) requires timely filing of all periodic reports. A late filing triggers a deficiency notice from Nasdaq, and if the company does not cure the deficiency within the prescribed period, delisting proceedings begin. NYSE has parallel requirements.

SEC comment letters and enforcement. The SEC's Division of Corporation Finance monitors late filings and can issue comment letters. Repeated or egregious late filings can escalate to enforcement referrals.

EDGAR Next credential risk. The SEC's EDGAR Next initiative, rolling out through 2026, modernizes account management and filing access controls. Companies that have not updated their authorized user lists under the new system risk submission failures at deadline, which the SEC will treat as a late filing regardless of the cause. Update your EDGAR credentials now at EDGAR Next.

2026 SEC Filing Deadlines: Quick-Reference Summary

FAQ

What is the SEC filing deadline for a large accelerated filer's 10-K in 2026? For a December 31, 2025 fiscal year-end, the 10-K is due March 2, 2026, 60 calendar days from year-end under Rule 13a-1. No 2026 federal holidays affect this specific date.

What happens if you miss the SEC filing deadline? A late periodic report triggers loss of Form S-3 eligibility for 12 months, a Nasdaq or NYSE deficiency notice, and potential SEC comment letters or enforcement referral. The consequences are cumulative and begin immediately on the day after the deadline.

What are the EDGAR filing hours in 2026? EDGAR accepts filings from 6:00 a.m. to 10:00 p.m. ET on business days. The critical cutoff is 5:30 p.m. ET: filings submitted after that time (except Section 16 forms) receive the next business day's date, which can create a technical late filing.

Are there SEC filing holidays in 2026? Yes. EDGAR is closed on all 11 federal holidays in 2026. When a deadline falls on a holiday or weekend, it rolls to the next business day. Key dates to watch: Independence Day is observed July 3 (Saturday July 4 moves to Friday), and Thanksgiving is November 26.

How does the NT 10-K extension work in 2026? Filing Form 12b-25 (NT 10-K) within one business day of the original deadline grants 15 additional calendar days for the 10-K, or 5 additional days for the 10-Q. The extension does not guarantee SEC acceptance and does not preserve S-3 eligibility if the company ultimately files late.

When is Form 13F due in 2026? Form 13F is due 45 calendar days after each calendar quarter-end: February 14 (Q4 2025), May 15 (Q1 2026), August 14 (Q2 2026), and November 14 (Q3 2026).

The 2026 compliance calendar has more moving parts than any prior year, with new 8-K cybersecurity obligations, Rule 10b5-1 quarterly disclosures, and the EDGAR Next credential transition all running alongside the standard periodic reporting clock. Build the calendar backward from each deadline, assign ownership, and treat 5:00 p.m. ET on deadline day as the finish line.