SEC Filings: 10-K, 10-Q, and 8-K
The three reports US public companies file most often, what each contains, when each is due, which 8-K items are worth watching, and a proposed change to quarterly reporting.
The short version
US public companies file an annual report on Form 10-K with audited financial statements, quarterly reports on Form 10-Q with unaudited statements for the first three quarters, and current reports on Form 8-K, generally within four business days, when major events happen. Deadlines depend on the company's size. Some 8-K items deserve special attention, such as a warning that past financial statements can't be relied on. In May 2026 the SEC proposed letting companies report twice a year instead of quarterly, but that hasn't been adopted.
By the end of this lesson, you'll be able to
- Describe what the 10-K, 10-Q, and 8-K each contain
- State the filing deadlines and how they depend on company size
- Recognize the 8-K items that most deserve attention
Why this matters
A company's filings with the SEC are the most complete and reliable record of its business, and they're free for anyone to read. Three forms do most of the work: the annual report, the quarterly report, and the current report on major events. Knowing what's in each, and when it arrives, tells you where to look and when.
The rules in this lesson apply to US public companies and can change. Check SEC.gov for the current requirements.
The three main reports
| Form 10-K | Form 10-Q | Form 8-K | |
|---|---|---|---|
| What it is | Annual report | Quarterly report, for the first three quarters | Current report on a major event |
| Financial statements | Audited | Unaudited | Only if the event calls for them |
| Main contents | Business, risk factors, management's discussion, full financial statements and notes | A shorter version of the 10-K for the quarter | The event and its terms |
| When it's due | 60 to 90 days after the year ends | 40 or 45 days after the quarter ends | Generally within four business days of the event |
The 10-K requires audited financial statements and covers the business, its risks, and management's view of the year.1 The 10-Q. The quarterly report a US public company files with the SEC for each of the first three quarters of its fiscal year. Its financial statements are unaudited. Glossary includes unaudited financial statements and is filed for each of the first three quarters of the fiscal year, since the 10-K covers the fourth.2 It gives a shorter version of the 10-K's disclosure, including financial statements, management's discussion, and risk factors.3 The 8-K. A current report a US public company files with the SEC to announce major events, such as an acquisition, a change of executives, or quarterly results, generally within four business days. Glossary lets companies report major events promptly instead of waiting for the next quarterly or annual report, and most 8-K disclosures are due within four business days of the event.4
The rest of this lesson is for members
Still to come in this lesson: Deadlines depend on size, 8-K items worth watching, A proposed change to quarterly reporting, the key takeaways, and 2 quiz questions with explanations.
Membership opens every lesson in the curriculum, the capstone projects, the interactive tools, and the members-only channels in the Hyperion Entities Discord. The first lesson of every module stays free.
Go deeper
- Reading a Real 10-K, Section by Section coming soonResearch Workshop (depth track)
- Disclosure Rules coming soonEthics, Regulation, and Market Integrity (depth track)
- How Securities Regulation Works coming soonEthics, Regulation, and Market Integrity (depth track)
Notes and sources
- U.S. Securities and Exchange Commission, Office of Investor Education and Advocacy. Investor Bulletin: How to Read a 10-K. Checked 2026-10-11. Back to text
- Investor.gov, U.S. Securities and Exchange Commission. Form 10-Q. Checked 2026-10-01. Back to text
- Investor.gov, U.S. Securities and Exchange Commission. How to Read a 10-K/10-Q. Checked 2026-09-30. Back to text
- U.S. Securities and Exchange Commission, Office of Investor Education and Advocacy. Investor Bulletin: How to Read an 8-K. Checked 2026-10-11. Back to text
- U.S. Securities and Exchange Commission, Division of Corporation Finance. Financial Reporting Manual, Topic 1 (Section 1330.1: filing deadlines). Checked 2026-10-01.
- Legal Information Institute, Cornell Law School. 17 CFR 240.0-3: Filing of material with the Commission. Checked 2026-10-01.
- U.S. Securities and Exchange Commission. SEC Proposes Amendments to Permit Optional Semiannual Reporting for Public Companies (May 5, 2026). Checked 2026-10-01.