A.O. Smith Water Heater Warranty Guide
Manufactured by A.O. Smith Corporation · Warranty info last verified: March 2026
Quick Warranty Facts
Tank / H.E. Coverage
6–15 years
Parts Coverage
10 years max
Labor Coverage
1 year
Transferable
No
Extended Warranty
Available
Registration Required
Recommended
Warranty by Product Line
Coverage periods vary by model series. Check your model against the table below.
| Product Line | Tank / H.E. | Parts | Labor |
|---|---|---|---|
Signature 100 Entry-level residential line. | 6 yr | 6 yr | 1 yr |
Signature 300 Mid-tier residential line with added features. | 9 yr | 9 yr | 1 yr |
Signature Premier Premium residential line with advanced features. | 10 yr | 10 yr | 1 yr |
Gas Tankless 15-year heat exchanger warranty is among the longest for gas tankless units. | 15 yr | 5 yr | 1 yr |
Hybrid Heat Pump (NEXT Hybrid) Qualifies for federal tax credits. High-efficiency heat pump technology. | 10 yr | 10 yr | 1 yr |
How to Register Your A.O. Smith Water Heater
Product registration is strongly recommended, even if not strictly required. It ensures A.O. Smith has your information on file for warranty service and safety notifications.
You will need:
- Serial number (from the rating label)
- Model number
- Installation date
- Installer's name and contact info
- Your name and address
What's Covered
- Defects in materials and workmanship
- Tank leaks from manufacturing defects (during tank warranty period)
- Internal component failures under normal use
- Heat exchanger failure (for tankless units)
- Manufacturer's defects discovered during warranty period
What's NOT Covered
- Improper installation not meeting local codes
- Lack of required maintenance (anode rod replacement, sediment flushing)
- Commercial use of residential-rated models
- Damage from sediment, scale, or water quality issues
- Units installed outside the US or Canada without authorization
- Labor after the first year
Extended Warranty: A.O. Smith Extended Warranty
Cost Range
$100–$200 (estimated)
Additional Years
+4 years
Includes Labor
No
Buy at Install
No
Optional extended warranty coverage adding years to tank and parts coverage. Contact A.O. Smith or your dealer for current availability and pricing.
How to File a A.O. Smith Warranty Claim
- 1
Register your product at aosmith.com/register
- 2
Locate serial and model numbers on the rating plate
- 3
Contact A.O. Smith support at 800-527-1953
- 4
A service technician will diagnose the issue
- 5
Warranty parts are shipped to the authorized service provider
- 6
Labor costs after year one are the homeowner's responsibility
A.O. Smith warranty line: 800-527-1953
Warranty Transferability: No
Warranty does not transfer to subsequent owners. Only the original purchaser is covered.
If you recently bought a home with a A.O. Smith water heater, the warranty likely did not transfer to you. Check the age of the unit with our free tool and consider a home warranty plan if the unit is aging.
Additional Notes
A.O. Smith Corporation is one of the world's largest water heater manufacturers and also produces heaters under the State, American, Reliance, Whirlpool, Craftmaster, and Lochinvar brand names. Warranty terms vary by brand and product line even within the A.O. Smith family. Always check the specific warranty certificate that came with your unit.
Related brands with similar warranty terms:
A.O. Smith Warranty FAQ
How long is the warranty on a A.O. Smith water heater?
A.O. Smith water heater warranties range from 6 to 15 years for tank coverage, depending on the model series. Parts are typically covered for 10 years and labor for 1 year(s).
Is a A.O. Smith water heater warranty transferable?
No. A.O. Smith warranties are not transferable. Warranty does not transfer to subsequent owners. Only the original purchaser is covered.
How do I check if my A.O. Smith water heater is still under warranty?
Use our free serial number decoder at WaterHeaterChecker.com to find your manufacture date, then compare the age to A.O. Smith's warranty period for your model. You can also contact A.O. Smith directly at 800-527-1953 with your serial number.
What voids a A.O. Smith water heater warranty?
Common warranty voiding issues for A.O. Smith include: Improper installation not meeting local codes; Lack of required maintenance (anode rod replacement, sediment flushing); Commercial use of residential-rated models.
Does A.O. Smith offer an extended warranty?
Yes. A.O. Smith offers A.O. Smith Extended Warranty: Optional extended warranty coverage adding years to tank and parts coverage. Contact A.O. Smith or your dealer for current availability and pricing. Cost range: $100–$200 (estimated).
What do I do if my A.O. Smith water heater fails under warranty?
Register your product at aosmith.com/register. Then locate serial and model numbers on the rating plate. Contact A.O. Smith at 800-527-1953 for assistance.
More for Your A.O. Smith Water Heater
Not sure which A.O. Smith model you have?
Check your A.O. Smith water heater's age, model info, and estimated warranty status with our free serial number decoder.
Decode Your A.O. Smith Serial NumberThis information is provided as a helpful reference only. Warranty terms are set by A.O. Smith and may change at any time. Always refer to the warranty certificate that came with your water heater for the definitive terms of your coverage. WaterHeaterChecker.com is not affiliated with A.O. Smith or A.O. Smith Corporation.