How long is the A.O. Smith water heater warranty?
A.O. Smith tank water heaters carry 6, 8, 10, or 12-year tank warranties depending on the model tier — the Signature series sold at Lowe's maps roughly to 6/9/12-year tiers. Parts typically carry 6 years; labor is generally not covered after the first year. Tankless models carry longer heat-exchanger terms (up to 15 years on some condensing models). Your exact term is printed on the rating plate sticker on the tank.
Like Rheem, A.O. Smith ties coverage to professional installation in accordance with local codes — homeowner self-installs can reduce or void coverage. The tank warranty covers leaks from tank failure; it does not cover sediment-related failures where annual flushing was neglected, and anode rod replacement is considered owner maintenance. A.O. Smith also makes State and American-branded water heaters with parallel warranty structures.
How to file an A.O. Smith warranty claim
Find your proof of purchase
Locate the receipt, order confirmation, or card statement showing the purchase date — coverage is measured from it.
Locate the model & serial number
Usually on a label on the unit, in the manual, or in your online account. A.O. Smith support will ask for it first.
Contact A.O. Smith through an official channel
Use the support number or claim form on their official site — not third-party sellers — so your claim is on record with the manufacturer.
Document everything
Save case numbers, names, dates, and photos of the defect. A clear paper trail resolves disputes faster.
Escalate if needed
If a valid claim stalls, ask for a supervisor and reference your statutory rights as a consumer (see our warranty types guide).
Full A.O. Smith claim guide, step by step →
Repair or replace your A.O. Smith? A quick rule of thumb
The common guidance: if the repair costs more than half the price of a new unit, or the unit is past ~75% of its expected lifespan, replacement usually wins. For major sealed-system or compressor failures out of warranty, repairs can run $400–$1,000+, which often tips toward replacing — but always get a diagnosis first.
When the warranty ends
Out of warranty or claim denied? Here's how to think through the options — ranked by what usually makes financial sense first.
A.O. Smith systems need a licensed HVAC tech — get a diagnosis and quote before deciding.
Find a local HVAC pro →A home warranty with system coverage handles A.O. Smith repairs and replacements — valuable given HVAC repair costs.
Compare home warranty plans →A failing A.O. Smith system past 12–15 years is often cheaper to replace. Get install quotes to compare.
Get replacement quotes →Some links are affiliate links — we may earn a commission at no extra cost to you. Affiliate disclosure.