"Warranty void if you use other parts"? What the law actually allows
Buying a generic filter, a third-party ink cartridge or using an independent repair shop can save real money. Many shoppers hold back because they're afraid of voiding the warranty. A federal law limits how far a manufacturer can push that threat.
- A warrantor generally can't condition a written or implied warranty on your use of a brand-name article or service, unless it provides that article or service free under the warranty.
- The FTC can waive the rule only if the product will work properly only with that brand and a waiver is in the public interest.
- FTC rules say a clause like "void if serviced by anyone other than an authorized dealer" is prohibited where those parts or services aren't covered by the warranty.
- The tying ban applies to warranties on consumer products costing more than $5.
The rule in plain English
15 U.S.C. 2302(c), Magnuson-Moss Warranty Act ban on tying says no warrantor of a consumer product "may condition his written or implied warranty" on the consumer's use of "any article or service (other than article or service provided without charge under the terms of the warranty) which is identified by brand, trade, or corporate name." The section applies to warranties on products "actually costing the consumer more than $5."
The FTC's example
The FTC's interpretation in 16 CFR 700.10, prohibited tying says no warrantor may condition the continued validity of a warranty "on the use of only authorized repair service and/or authorized replacement parts for non-warranty service and maintenance." It gives an example of a prohibited clause: "This warranty is void if service is performed by anyone other than an authorized 'ABC' dealer and all replacement parts must be genuine 'ABC' parts." The FTC adds that such provisions are also deceptive, because a warrantor can't legally avoid liability where "a defect is unrelated to the use by a consumer of 'unauthorized' articles or service."
What it doesn't cover
- Free parts or service: if the warranty provides the part or service at no charge, the warrantor can require it.
- Waivers: the FTC can grant a waiver if the warrantor shows the product "will function properly only if" the named article or service is used, and the FTC finds a waiver is in the public interest.
- Damage caused by the part: the rule protects you when a defect is unrelated to the third-party part. If a bad part actually causes the damage, that repair may not be covered.
How to use this when you save
- Keep receipts for parts and service, and note that they meet the maker's specs.
- If a claim is denied only because you used another brand or shop, ask the warrantor to explain in writing how that caused the defect.
- Read the warranty itself. Some cover parts only, and FTC rules say a parts-only warranty can't force you to use the maker's labor to install the replacement parts.
Related: how to claim rebates and disputing a card charge.
General consumer information, not legal advice. Sources: 15 U.S.C. 2302(c), Magnuson-Moss Warranty Act ban on tying; 16 CFR 700.10, prohibited tying.
Published October 31, 2026. We do not use affiliate links on this page; see our Affiliate Disclosure.