10-K vs 10-Q vs 8-K: SEC Filing Types Explained for Investors (2026)

The SEC requires public companies to file dozens of different form types, but three dominate every investor’s workflow: the 10-K (annual report), the 10-Q (quarterly report), and the 8-K (current report). Together they create a continuous picture of a company’s financial condition, operating performance, and material events.

Most investors know these forms exist. Far fewer understand the structural differences that determine when each is filed, what it legally must contain, how thoroughly it’s been audited, and most importantly — what to look for in each. This guide covers all of that.

Quick Comparison Table

Before diving into each, here’s how they stack up on the dimensions investors care about most:

What is a 10-K Filing?

The 10-K is the gold standard of public company disclosure. Filed once per year within 60 or 90 days of the fiscal year end (depending on company size), it’s the most comprehensive document a public company produces and the only filing that contains fully audited financial statements.

What a 10-K must include

The SEC mandates specific content in every 10-K. The document is organized into four numbered parts:

• Part I: Business overview (Item 1), risk factors (Item 1A), properties (Item 2), legal proceedings (Item 3), mine safety disclosures (Item 4 — relevant only to mining companies)
• Part II: Market for common equity (Item 5), selected financial data (Item 6), MD&A (Item 7), quantitative and qualitative disclosures about market risk (Item 7A), financial statements and supplementary data (Item 8), internal controls over financial reporting (Item 9A)
• Part III: Directors and executive officers (Item 10), executive compensation (Item 11), security ownership (Item 12), related-party transactions (Item 13), principal accountant fees (Item 14)
• Part IV: Exhibits and financial statement schedules (Item 15)

What makes the 10-K uniquely valuable

Three things appear in the 10-K and nowhere else in periodic reporting:

1. Audited financials. The independent auditor has verified the numbers. This is the only annual filing that provides this assurance.
2. Full risk factor disclosure. The 10-Q only requires disclosure of material changes to risk factors from the last 10-K. The 10-K must include the complete, current list.
3. Going concern language. If the auditor has substantial doubt about the company’s ability to operate for the next 12 months, it appears in the auditor’s report within the 10-K. This is a five-alarm signal that rarely appears in a 10-Q.

When a 10-K matters most

The 10-K is the baseline document. Read it when you’re initiating coverage of a new company or haven’t reviewed a holding in 12 months. It resets your understanding of the business model, the risk landscape, and the financial trajectory. Once you have a 10-K baseline, the 10-Qs and 8-Ks throughout the year are easier to evaluate in context.

What is a 10-Q Filing?

The 10-Q is filed for each of the first three fiscal quarters — Q1, Q2, and Q3. There is no Q4 10-Q: the fourth quarter is covered in the annual 10-K, which is filed a few months after the fiscal year ends. Companies therefore file three 10-Qs and one 10-K per year, giving investors four periodic financial snapshots annually.

What a 10-Q must include

A 10-Q is lighter than a 10-K but still covers significant ground:

• Unaudited financial statements for the quarter and year-to-date period, with comparative prior-year figures
• MD&A covering the quarter’s results, liquidity, and capital resources
• Quantitative and qualitative disclosures about market risk (if materially changed)
• Legal proceedings update — new material litigation must be disclosed
• Risk factors — only material changes since the last annual report need to be listed
• Controls and procedures — management’s evaluation of disclosure controls effectiveness
• CEO/CFO certifications under Sarbanes-Oxley Section 302 (the same attestations as in the 10-K)

The unaudited caveat — how much does it matter?

The 10-Q’s financials are reviewed, not audited. Under PCAOB standards, a review involves inquiries and analytical procedures, not the in-depth testing of an audit. In practice, the risk is low for most large, established companies with strong internal controls and institutional auditors. But for smaller companies, micro-caps, or companies that have disclosed internal control weaknesses, the unaudited status is a real caveat to keep in mind.

What to look for in a 10-Q

The highest-value information in a 10-Q relative to the last 10-K:

• Revenue and margin versus the prior year quarter. Is the trend improving or deteriorating?
• Working capital changes. Receivables or inventory growing faster than revenue is an early warning.
• New risk factors or language changes. Additions signal management’s updated view of the threat landscape.
• Contingencies and litigation updates. New lawsuits or regulatory proceedings appear in footnotes, not headlines.
• Guidance language in MD&A. Management often drops or reinforces forward-looking commentary quarter by quarter. Tone shifts matter.

What is an 8-K Filing?

The 8-K is the most time-sensitive SEC filing. Unlike the periodic 10-K and 10-Q, which follow a predictable calendar, the 8-K is event-driven: it must be filed within 4 business days of a material event. If you see a stock moving sharply and want to know why, an 8-K is often the first place to look on EDGAR.

What triggers an 8-K

The SEC specifies more than 25 events that require an 8-K. The most market-moving categories:

• Earnings releases (Item 2.02). When a company issues a press release about its quarterly or annual results, that press release is attached as an exhibit to an 8-K. This is the most common 8-K trigger and the reason most 8-Ks hit EDGAR on earnings day.
• Acquisitions and dispositions (Item 2.01). Completion of a merger, acquisition, or material asset sale. This often accompanies major strategic news before a formal 10-Q/10-K can reflect the transaction.
• Entry into or termination of a material agreement (Item 1.01 / 1.02). A significant customer contract, credit agreement, or partnership that could affect the business must be disclosed.
• Bankruptcy or receivership (Item 1.03). Some investors first learn of a bankruptcy filing through a company’s own 8-K.
• Director/officer departures and appointments (Item 5.02). CFO departures in particular are watched closely. A CFO leaving abruptly near a fiscal quarter end is a well-known red flag.
• Amendment to articles or bylaws (Item 5.03). Governance changes, including anti-takeover provisions, show up here.
• Other material events (Item 8.01). A catch-all for anything the company determines is material but doesn’t fit other categories. Activist investor letters, SEC investigations, and cybersecurity incidents commonly appear here.

8-K vs press release — what’s the difference?

A press release is marketing. An 8-K is a legal disclosure. The practical difference: an earnings press release can frame numbers any way management wants (and typically does, by leading with adjusted EBITDA). But the financial statements attached as an exhibit to the 8-K must conform to GAAP. The press release highlights what management wants investors to see. The 8-K exhibit is what they’re legally required to show.

Sophisticated investors read both — looking for gaps between the press release narrative and the underlying numbers in the exhibit.

8-K filings as a real-time monitoring tool

Because 8-Ks are filed within 4 business days of a material event, they function as a near-real-time monitoring mechanism. EDGAR’s full-text search and RSS feeds allow investors to set up alerts for specific companies or industries. An 8-K from a company you don’t own can also provide market intelligence — a supplier announcing supply chain disruptions affects downstream customers; a competitor announcing a major customer win signals something about the competitive environment.

The Filing Calendar: When to Expect Each

Understanding the typical filing calendar helps investors know when to look for new disclosures. Using a December 31 fiscal year as an example (the most common calendar among large US public companies):

• February–March: Q4/full-year earnings → 8-K (earnings release). 10-K due by March 1 (large accelerated filers) or March 31 (others).
• May: Q1 earnings → 8-K. 10-Q due within 40–45 days of March 31.
• August: Q2 earnings → 8-K. 10-Q due within 40–45 days of June 30.
• November: Q3 earnings → 8-K. 10-Q due within 40–45 days of September 30.
• Year-round: 8-Ks for material events (acquisitions, management changes, agreements).

Companies with non-December fiscal year ends (many retailers use January; many tech companies use March or September) shift this calendar, but the relative deadlines are identical.

How to Use All Three Together

The most effective approach treats the three filings as a system, not three separate documents:

1. Start with the 10-K. This is your baseline. Read it when you first establish coverage of a company. Understand the business model, the key risk factors, the financial history, and management’s track record of hitting guidance. Everything in the 10-Qs and 8-Ks for the next 12 months will be interpreted against this baseline.
2. Monitor with 10-Qs. Three times per year, compare the quarter’s MD&A and financials to your baseline. Look for deterioration or improvement in the metrics that matter most for this specific business. Note any new risk factors — even one new sentence in risk factors can be highly informative about management’s current concerns.
3. React to 8-Ks in real time. Set up alerts (EDGAR RSS, financial data platforms) so you see 8-Ks within hours of filing. An 8-K before market open is often the reason a stock gaps up or down. Reading the underlying exhibit is almost always more informative than reading a news summary about it.

Beyond the Big Three: Other SEC Filings Investors Should Know

While 10-K, 10-Q, and 8-K cover most of what investors need, a few other forms appear regularly enough to recognize:

• DEF 14A (Proxy statement). Filed before the annual shareholder meeting. Contains full executive compensation details, director biographies, and shareholder proposal outcomes. The source of truth for compensation benchmarking.
• S-1 / S-11 (IPO registration). The registration statement for a public offering. Structurally similar to a 10-K but filed before a company is public. IPO investors should treat it as their first “10-K.”
• SC 13D / 13G. Filed when an investor acquires more than 5% of a company’s shares. 13D is the activist version; 13G is the passive version. Major activist campaigns begin with a 13D filing.
• Form 4. Insider trades. Filed within 2 business days of a transaction by directors, officers, or 10%+ shareholders. Cluster buying by multiple insiders is one of the best signals in public markets.
• NT 10-K / NT 10-Q. A notification that a company will be late filing its periodic report. Late filings are a yellow flag — sometimes benign (auditor delay on complex transaction), sometimes a signal of accounting issues.

Common Mistakes Investors Make with SEC Filings

Understanding what each filing is doesn’t prevent these common errors:

• Relying on press releases instead of the underlying exhibit. The 8-K exhibit filed with the SEC is a legal document; the press release is not. For anything material, always verify against the EDGAR document.
• Skipping the 10-K once you’ve “done the research.” Companies change. Risk factors that weren’t in last year’s 10-K, competitor dynamics, management compensation structures — these evolve. Annual 10-K review for every holding is minimum viable due diligence.
• Treating 10-Q and 10-K financials as equivalent. The 10-Q is unaudited. For most large companies this is a minor caveat; for companies with internal control disclosures, it matters.
• Missing the 8-K on the evening before market open. Earnings 8-Ks frequently hit EDGAR after the close, before the following morning’s earnings call. The market opens with price discovery already partly done based on the 8-K. Reading the 8-K exhibit before the call is better than reading a news summary after.
• Searching only in text, not in exhibits. Material information can be buried in exhibits attached to a filing rather than the body of the document itself. Material agreements, audit reports, and earnings press releases are all in exhibits.

How AI Tools Change the 10-K / 10-Q / 8-K Workflow

Tracking three filing types across 30+ holdings manually isn’t realistic for most investors. Modern AI tools have changed the workflow significantly. Instead of reading every filing from scratch, investors increasingly use AI-powered summaries as a first pass — surfacing changed risk factors, unusual MD&A language, and financial trend flags — then drilling into the underlying document only when the AI flags something worth investigating.

For the 8-K specifically, AI parsing is particularly valuable for the “Other Events” category (Item 8.01), which can contain anything from a cybersecurity incident to an SEC investigation to a major supply contract. Natural language summaries of 8-K exhibits help investors extract the signal in under a minute per filing rather than reading the entire document.

TL;DR Filing applies this approach across all three filing types for every public company — search any ticker to see the most recent 10-K summary, 10-Q highlights, and 8-K alerts side by side.

Frequently Asked Questions

What is the difference between a 10-K and a 10-Q?

A 10-K is the annual report, filed once per year, containing audited financial statements, full risk factor disclosure, and executive compensation details. A 10-Q is the quarterly report, filed three times per year, containing unaudited quarterly financials and a lighter set of disclosures. The 10-K is the baseline document; the 10-Q tracks quarterly performance against it.

What triggers an 8-K filing?

Over 25 specific events require an 8-K within 4 business days: earnings releases, acquisitions and dispositions, entry into material agreements, bankruptcy, director/officer appointments or departures, amendments to governance documents, and other events the company deems material. Earnings 8-Ks are the most common; material agreement and management change 8-Ks are the most market-moving outside of earnings season.

Is the 10-Q audited?

No. The 10-Q contains unaudited interim financials. The company’s auditors conduct a review (inquiries and analytical procedures) rather than a full audit. Only the annual 10-K contains audited financials. For companies with disclosed internal control weaknesses, this distinction matters more than for established large caps.

How many 10-Qs does a company file per year?

Three — for Q1, Q2, and Q3. The fourth quarter is not covered by a standalone 10-Q. Instead, Q4 results appear in the annual 10-K, which is filed after the fiscal year ends. Combined with the 10-K, investors receive four periodic financial snapshots per year.

Where can I find 10-K, 10-Q, and 8-K filings?

All SEC filings are available free at EDGAR (sec.gov). You can search by company name or ticker and filter by form type. TL;DR Filing also provides AI-powered summaries of all three filing types for every US public company, surfacing changes and red flags automatically so you don’t have to read every page. Try it for any ticker →

How to Analyze Each Filing Once You Find It

For a step-by-step guide to extracting the highest-value information from a 10-K in under 10 minutes, see our Investor’s 7-Point 10-K Checklist. The checklist covers which sections matter most (Item 1A risk factors, MD&A, three-year financial trends), what to skip, and the specific red flags that warrant deeper investigation before making an investment decision.