Compare · MRK and PFE
Merck vs. Pfizer
Revenue, growth, margins, cash flow and cash returned, side by side from each company's latest annual report.
Merck's medicines are led by Keytruda for cancer, and it sells vaccines including Gardasil; it also has an Animal Health business. Pfizer groups its medicines into primary care, specialty care and oncology, with Eliquis, Prevnar and Comirnaty among them. Below are the figures each one reported in its latest annual report (Form 10-K), side by side, with links to the filing behind every number. Both fiscal years end in December, so the periods line up. Why fiscal years differ.
Comparing Merck fiscal 2025 (ended Dec 31, 2025) with Pfizer fiscal 2025 (ended Dec 31, 2025)
MerckPfizer
Each pair of bars shows both companies on one scale.
Revenue and growth
| Company | Prior year | Latest year | Change |
|---|---|---|---|
| Merck (FY2024 to FY2025) | $64.2B | $65.0B | +1.3% |
| Pfizer (FY2024 to FY2025) | $63.6B | $62.6B | −1.6% |
Merck reports sales: sales of prescription medicines, vaccines and animal health products, plus some alliance revenue. Pfizer reports total revenues: sales of prescription medicines and vaccines, plus alliance and royalty revenue.
Margins
| Company | Revenue | Net income | Net margin |
|---|---|---|---|
| Merck FY2025 | $65.0B | $18.3B | 28.1% |
| Pfizer FY2025 | $62.6B | $7.8B | 12.4% |
Operating income is shown only when both companies report it as a line in their income statement.
Margin is the profit line divided by revenue, worked out by Ticker Sage from the linked figures. What profit margins measure.
Cash flow and cash returned
| Company | Cash from operations | Capital spending | Free cash flow | Buybacks | Dividends paid |
|---|---|---|---|---|---|
| Merck FY2025 | $16.5B | $4.1B | $12.4B | $5.1B | $8.2B |
| Pfizer FY2025 | $11.7B | $2.6B | $9.1B | – | $9.8B |
Capital spending is property and equipment for both companies, as each company labels it in the cash flow statement. Free cash flow isn't a GAAP line; Ticker Sage works it out the same way for both. A dash means the company's filing data has no figure for that line. How free cash flow works · How buybacks work · How dividends work.
How each one makes money
Merck
Merck reports two operating segments. Pharmaceutical covers human health medicines and vaccines, led by Keytruda for many types of cancer, the Gardasil HPV vaccines, the childhood vaccines ProQuad, M-M-R II and Varivax, and newer products such as Winrevair for pulmonary arterial hypertension. Animal Health sells vaccines and medicines for livestock and pets.
It sells mostly to drug wholesalers, retailers, hospitals, governments and health care providers. Its fiscal year is the calendar year.
Pfizer
Its Biopharma segment groups products into Primary Care (including Eliquis, Prevnar, Comirnaty and Paxlovid), Specialty Care (including Vyndaqel) and Oncology (including Padcev and Ibrance). Pfizer CentreOne makes medicines for other companies.
Its fiscal year is the calendar year.
Main risks each one lists
Merck
- Sales of a product usually fall fast once patent protection ends; Keytruda is its largest product by far.
- US Medicare price negotiation, government pricing rules and payer pressure can cut prices.
- Drug development is costly and uncertain, and many candidates fail or are delayed.
- Buying companies and licensing products can bring large charges, and the deals may not deliver the expected sales.
- Problems at plants or suppliers could interrupt supply of medicines and vaccines.
Pfizer
- Several large drugs lose patent protection in the next few years.
- US pricing laws and pressure from insurers and governments can cut revenue.
- New drugs can fail in trials or regulatory review.
- Demand for Comirnaty and Paxlovid has fallen and is hard to predict.
- Products and manufacturing face strict oversight.
How they differ
- Size. Merck reported $65.0B of revenue for fiscal 2025, and Pfizer $62.6B for fiscal 2025.
- Growth. Merck's revenue grew 1.3% in its latest year and Pfizer's fell 1.6%.
- Margins. Pfizer kept 12.4% of revenue as net income and Merck 28.1%.
- Animal health. Merck has an Animal Health segment for livestock and pets.
- Manufacturing for others. Pfizer CentreOne makes medicines for other companies.
Differences in size, growth or margin describe the past year only. None of this says which business will do better.
Sources
- Merck Form 10-K for fiscal 2025, filed Feb 24, 2026
- Pfizer Form 10-K for fiscal 2025, filed Feb 26, 2026
Merck company file → · Pfizer company file →
Common questions
Which is bigger by revenue, Pfizer or Merck?
Merck reported $65.0B of revenue for fiscal 2025 and Pfizer $62.6B for fiscal 2025.
Do Merck and Pfizer both sell vaccines?
Yes. Merck's include Gardasil and the childhood vaccines ProQuad, M-M-R II and Varivax; Pfizer's include Prevnar and Comirnaty.
How do their profit margins compare?
In the latest fiscal year Pfizer's net margin was 12.4% and Merck's was 28.1%, worked out from the net income and revenue in each 10-K.
Where do these numbers come from?
From each company's latest Form 10-K filed with the SEC. Every figure on this page links to the filing it came from.
Disclosures
- Editor holdings
- The editor holds no position in any company named on this page. As of Oct 25, 2026.
- Compensation
- Nobody paid for this page. No affiliate links on this page.
- Sources
- Each company's own SEC filings, linked next to each number.
- Last updated
- Oct 26, 2026
General education, the same for every reader. Not a recommendation to buy, sell or hold any security, and it doesn't consider your situation.
More in Learn · Methodology & Disclosures explains where every number comes from.