Explainer
The federal crib mattress standard, explained
Every crib mattress sold in the U.S. must meet a mandatory federal standard, 16 CFR part 1241, enforced by the Consumer Product Safety Commission. This page explains what the rule's text says, what changed in 2026, and what to check before you buy.
Everything here comes from the rule's current text in the eCFR and the Federal Register's record of the February 12, 2026 notice. We are not a testing lab, and we have not tested any mattress.
At a glance
Which version applies
| In effect from | Standard incorporated | Source |
|---|---|---|
| August 15, 2022 | ASTM F2933-21, with CPSC modifications, at 16 CFR part 1241 | Federal Register, February 12, 2026 and eCFR |
| CurrentMay 3, 2026 | ASTM F2933-25, approved October 1, 2025, with certain CPSC modifications kept | Federal Register, February 12, 2026 and eCFR |
The ASTM standard itself is a separate document that the rule incorporates by reference. We describe only what the rule's own text and the Federal Register record say.
The rule
What the rule says
Scope. The rule covers all crib mattresses within the scope of ASTM F2933, including full size crib mattresses, non-full-size crib mattresses, and after-market mattresses for play yards and non-full-size cribs.
The core requirement. Each crib mattress must comply with ASTM F2933-25, with the CPSC's own additions and exclusions.
Size and fit. One of those CPSC additions: a full size crib mattress must measure at least 27 1/4 inches wide and 51 5/8 inches long, and when it is placed in the corner of the crib with the test sheet on, the corner gap must not exceed 3.15 inches. The test sheet is a fitted 100 percent cotton sheet, washed in hot water and dried at least twice.
Product registration. Crib mattresses are on the CPSC's list of durable infant or toddler products that need a consumer registration system, under 16 CFR part 1130.
What changed
The 2026 update
The CPSC's direct final rule of February 12, 2026 updated the mandatory standard to incorporate ASTM F2933-25, in place of the 2021 version, while keeping certain CPSC modifications. According to the Federal Register record, it took effect on May 3, 2026.
The rule's current text keeps the CPSC's own minimum size and corner gap requirements for full size mattresses. We have not read the full Federal Register notice or the ASTM document, so we do not list the technical changes inside the 2025 version.
The brands
What Avocado and Naturepedic state
Avocado
Avocado states that both sides of its Organic Crib Mattress have been independently tested and meet 16 CFR 1241, which incorporates ASTM F2933. It states the same for both sides of its Eco Organic Crib Mattress.
Check the price at AvocadoNaturepedic
Naturepedic states that its Classic, Breathable and Breathable Ultra crib mattresses meet CPSC and AAP guidelines for crib mattress firmness. Its pages do not name the rule by number.
Check the price at NaturepedicThese are the brands' own statements. We have not tested either mattress. To compare them on materials and terms, see best organic crib mattresses.
Before you buy
What to check on any crib mattress
- On the product pageLook for the standardA statement that the mattress meets 16 CFR 1241 or the CPSC crib mattress standard.
- Against your cribCheck the sizeA full size crib mattress must be at least 27 1/4 by 51 5/8 inches. Follow your crib maker's instructions too.
- On a two sided mattressFind the infant sideEvery two sided model we cover marks a firmer side for infants. Use the side the label names.
More in our crib mattress guides: Best organic crib mattresses, Avocado vs Naturepedic crib mattress, Crib mattress trials and warranties, Crib mattress certifications explained.
Common questions
Questions parents ask
Is there a federal standard for crib mattresses?
Yes. 16 CFR part 1241, a CPSC rule. It incorporates ASTM F2933 with CPSC modifications: the 2021 version from August 15, 2022, and the 2025 version since May 3, 2026.
Does the standard include firmness?
The rule's text incorporates the ASTM standard by reference, and we have not read the ASTM document, so we do not describe its tests. Avocado states that both sides of its crib mattresses passed firmness tests under 16 CFR 1241. Naturepedic states that its crib mattresses meet CPSC and AAP guidelines for crib mattress firmness.
What does the AAP recommend?
The AAP recommends that babies sleep on their backs on "a firm, flat noninclined surface" without soft bedding, and advises against products marketed to lower SIDS risk, which it says "may provide a false sense of security" (AAP, June 21, 2022). For advice about your baby, talk to your pediatrician.
Is an organic crib mattress held to a different standard?
No. The federal rule applies to every crib mattress, organic or not. Organic certifications cover materials, which is a separate question. Our certifications guide explains them.
Does this site test crib mattresses?
No. We report what the rule's text in the eCFR, the Federal Register and each brand publish, with the date we read it.
The short version
Two brands that state they meet the rule
Avocado states that both sides of its crib mattresses meet 16 CFR 1241. Naturepedic states that its crib mattresses meet CPSC and AAP firmness guidelines. Compare them on materials, price and terms in our crib mattress guide.
- 16 CFR part 1241
- ASTM F2933-25 since May 3, 2026