Prop 65 warning label, short-form, online and food rules

What a Prop 65 warning label must say and where it goes

A Prop 65 warning tells California consumers that a product can expose them to a chemical the state lists as causing cancer, birth defects or other reproductive harm. A standard consumer-product safe harbor warning names the chemical and the harm, with a triangle symbol, a signal word and www.P65Warnings.ca.gov (OEHHA regulations).

The short form that took effect January 1, 2025 names a chemical too. Products manufactured and labeled before January 1, 2028 can still carry the old chemical-free form. Food and other tailored warnings use their own wording.

When a California Prop 65 warning is required

A business that knowingly and intentionally exposes someone to a listed chemical must first give "a clear and reasonable warning" (California Attorney General's Prop 65 FAQ). No warning is needed below the safe harbor level: one excess cancer case in 100,000 people over a 70-year lifetime (the NSRL), or no observable reproductive effect at 1,000 times the exposure (the MADL). Businesses with nine or fewer employees are exempt. Penalties run up to $2,500 per day per violation. Meeting the applicable Article 6 rules makes the warning clear and reasonable under 27 CCR 25601(a) (final regulatory text).

Full-length Prop 65 warning label requirements

Section 25603(a) sets the consumer product warning in three parts (OEHHA regulations):

1. The symbol: a black exclamation point in a yellow equilateral triangle with a bold black outline. It goes to the left of the text and is no smaller than the height of the word "WARNING". If the label, sign or shelf tag isn't printed in yellow, the symbol can be black and white.
2. The signal word "WARNING:", "CA WARNING:" or "CALIFORNIA WARNING:", in bold capital letters. The CA options were added in 2024 for goods also sold outside California (FSOR).
3. The sentence. For a carcinogen: "This product can expose you to chemicals including [name of one or more chemicals], which is [are] known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov."

For reproductive toxicants the ending becomes "to cause birth defects or other reproductive harm." If the product exposes users to a carcinogen and a different reproductive toxicant, name one of each. If one chemical is listed for both, name it once and say "to cause cancer and birth defects or other reproductive harm." With a single chemical you may drop "chemicals including."

Use the chemical name as it appears on the Proposition 65 list (P65Warnings FAQ for businesses). The full-length warning has no set minimum point size. It still has to be "likely to be seen, read, and understood by an ordinary individual under customary conditions of purchase or use" compared with everything else on the label or sign (25601(c)). If the label gives consumer information in another language, the warning must appear in that language as well as English (25602(d)).

Where the warning can go

Under 25602(a) a consumer product warning can be given by any one of these methods (OEHHA regulations):

• a product-specific posted sign, shelf tag or shelf sign at each point of display
• an electronic device or process that gives the warning automatically before or during purchase, without the buyer looking for it (this one doesn't cover internet sales)
• the full-length warning on the product label
• the short-form warning on the product label

The short form is a label method only. Prop 65 signs and shelf tags use full-length content.

The new Prop 65 warning short form

OEHHA's amendments were approved on November 26, 2024 and took effect January 1, 2025 (OEHHA rulemaking page). The exemption that let a short-form warning leave out the chemical name was deleted (final regulatory text).

The current short-form label uses the symbol and a bold signal word ("WARNING:", "CA WARNING:" or "CALIFORNIA WARNING:"), plus one of these examples (final text).

The short form isn't limited to small packages. OEHHA allows it "on any size product" if type size complies. It no longer has to match the largest type used for other consumer information. The floor is 6-point, plus the 25601(c) conspicuousness test (FSOR).

The 2028 cutoff for the old short form

Section 25603(c) keeps the old wording for any product "manufactured and labeled prior to January 1, 2028," no matter when it's sold (OEHHA regulations). The old text is "WARNING:" plus "Cancer -- www.P65Warnings.ca.gov.", "Reproductive Harm -- www.P65Warnings.ca.gov." or "Cancer and Reproductive Harm -- www.P65Warnings.ca.gov." Only "WARNING:" works on that old label, not "CA WARNING:".

The sell-through period is unlimited for products made and labeled in time. But OEHHA declined to extend it to preprinted labels or packaging (FSOR). A roll printed in 2027 and applied in 2028 doesn't qualify.

Online sales and catalogs

For internet purchases, 25602(b) requires 25603 content on the product display page, a clearly marked hyperlink on that page using "WARNING", "CA WARNING" or "CALIFORNIA WARNING" that links to the warning, or a prominent warning before the purchase is complete. If the label uses the short form, the site may use that content (OEHHA regulations).

For safe harbor, OEHHA says the warning must be given "both on the internet website and on the product or with the product." Warnings sent by text or email don't qualify. A QR or barcode scan that isn't needed to finish the purchase "would not comply" (FSOR).

Retailers get a grace period. For internet purchases before January 1, 2028, a retail seller isn't responsible for posting the new short-form content online until 60 calendar days after it receives the updated warning or written notice (25602(b)(2)).

Catalogs must show the warning "in a manner that clearly associates it with the item being purchased" (25602(c)). A catalog can use the same short-form content as the product label (OEHHA regulations).

Who provides the Prop 65 warning

Section 25600.2 puts the main duty upstream. A manufacturer, producer, packager, importer, supplier or distributor complies by warning on the label or accompanying labeling, or by sending written notice to the retailer's authorized agent. The notice must say the product may cause an exposure, identify the product, and include all warning materials (including internet text). Renew it yearly during California sales, and within 90 days if a different chemical or endpoint is added (OEHHA regulations).

The retailer places and maintains the materials it receives, including online warnings. It warns on its own only for its own or a licensed brand, a chemical it knowingly introduced, a warning it covered or altered, or actual knowledge where no upstream business has a California agent or place of business. A written agreement can reallocate duties if the consumer still gets warned (25600.2).

Prop 65 warning on food

Food warnings, including for dietary supplements, follow 25607.2 and can use any method in 25602. On a food label the warning must be set off from surrounding information and enclosed in a box. There's no triangle symbol (OEHHA regulations; ISOR).

The full-length food warning uses "WARNING:", "CA WARNING:" or "CALIFORNIA WARNING:", then: "Consuming this product can expose you to chemicals including [name of one or more chemicals], which is [are] known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov/food." (food samples). Since January 1, 2025 food also has a short form: the same signal words, then a sentence such as "Cancer risk from exposure to [name of chemical]. See www.P65Warnings.ca.gov/food." Label only, 6-point minimum and still boxed (final regulatory text).

Acrylamide has tailored food wording in 25607.2(c), with a second option added January 1, 2025 (acrylamide FSOR). Alcoholic beverages have their own warning in 25607.4.

Tailored warnings and what may change

Where Article 6 has a tailored warning for an exposure, you must use it for safe harbor. Passenger and off-highway motor vehicle parts, and recreational marine vessel parts, got theirs on January 1, 2025 (25607.50-25607.53).

OEHHA's Omnibus 2026 draft of July 30, 2026 would add QR codes as a warning method. It's a pre-regulatory workshop draft, not law.

You can ask RegAffairs AI whether a chemical is listed for cancer, reproductive harm or both, and open the cited OEHHA sources.