Product warranties explained: what federal law requires before and after you buy

The warranty is part of what you pay for, and federal law sets rules for how it is offered. The Magnuson-Moss Warranty Act does not require any business to provide a written warranty. When a company does give one on a consumer product, the Act and the Federal Trade Commission's rules govern what it must disclose, when you can read it and what it cannot take away.

You can read it before you buy

If a consumer product costs more than $15, any written warranty on it has to be available for you to read before you buy, the FTC says. Its consumer advice adds that this holds online as well as in stores. Online, look for a warranty link on the product page or in the maker's legal pages.

The two makers in our Sonos and Bose soundbar comparison show two approaches. Bose states its one-year limited warranty on each soundbar page. Sonos sets out its warranty in its US terms, last updated in September 2026: one year from the original purchase, against defects in materials and workmanship.

Full or limited

On products costing more than $10, a written warranty must be titled either full or limited. A full warranty meets the federal minimum standards. A limited one falls short of at least one of them, and the title is there to tell you so. According to the FTC's guide for businesses, a full warranty must:

• cover anyone who owns the product while the warranty lasts
• make warranty service free
• let the consumer choose a replacement or a full refund if the product still cannot be repaired after a reasonable number of attempts
• ask nothing of the consumer as a condition of service beyond telling the company that service is needed, unless the company can show the duty is reasonable; a registration card that must be sent back is not allowed
• set no limit on how long implied warranties last

Bose's soundbar warranties are titled limited, which means they fall short of at least one of those standards, so read what the limits are: how long it lasts, what it excludes and what it asks of you.

Implied warranties still apply

Implied warranties apply even if a product has no written warranty, the FTC says. Under the warranty of merchantability, the seller promises that the product does what it is meant to do; the FTC's example is a toaster that toasts. The warranty of fitness for a particular purpose covers a product you buy because the seller advised that it suits a specific job.

They do not apply if the seller gives written notice that there is no warranty, or marks the product “as is”, where state law allows that. A company that offers a written warranty cannot disclaim or modify the implied warranties, under the Act. A limited warranty may cap how long they last at the length of the written warranty; a full warranty may not.

Outside parts and repairs cannot void it

Federal law generally bars these “tie-in” conditions: a maker cannot make your warranty depend on using particular parts or services, unless it supplies them free or the FTC has granted it a waiver.

The FTC has acted on this. In 2022 it acted against Weber-Stephen Products, the maker of Weber grills, together with Harley-Davidson and MWE Investments, the maker of Westinghouse outdoor power equipment, saying the three broke the law by telling customers their warranties would be void if they chose outside parts or repairs. Final orders approved on October 27, 2022 require new warranty language. Weber's must state:

Using third-party parts will not violate this warranty.

Where you buy can matter

Some warranties depend on the seller. Sonos's US terms say that buying a product from or through anyone other than Sonos or an authorized dealer or reseller voids any warranty Sonos would otherwise offer. The same section adds that its limitations do not apply to the extent a product meets the Magnuson-Moss Warranty Act's definition of a “consumer product”. The FTC's guide says the Act covers warranties on tangible property normally used for personal, family or household purposes. Before buying at a discount from a marketplace seller, check that the seller is authorized by the maker, and read the warranty terms.

Extended warranties are service contracts

Extended warranties and service contracts are bought separately, at extra cost, and the FTC notes that the warranty you already have may cover the same repairs for the same period. Service contracts also do not have to carry a full or limited title, or the standard disclosures that warranties must include.

Ask what a plan adds. On all three soundbars, the two-year plans begin after the one-year Bose warranty ends, while the three-year accident plans begin at purchase, so their first year runs alongside the Bose warranty. Compare the plan's price with the product's and with what the warranty already covers.

If something goes wrong

1. Contact the seller first.
2. If that does not resolve it, write to the manufacturer at the address in the warranty. The FTC suggests certified mail with a return receipt, so you can prove the letter arrived.
3. If the company still does not resolve it, report it to the FTC at ReportFraud.ftc.gov or to your state attorney general.