Terms of Use
Effective date: 21 July 2026
By using TankBirthday (tankbirthday.com), you agree to these terms. If you do not agree, please do not use the site.
What this site is
TankBirthday is a free reference tool that estimates a water heater's manufacture date from its serial number, along with general information about water heater brands and lifespans.
Estimates are for guidance only
Age results from our decoders are estimates and may be wrong. Manufacturers change their serial formats over time, some formats are reused, and some cannot be decoded to a single date. Bradford White is a well-known example: its letter-based year codes repeat roughly every 20 years, so the same serial can match a unit from 2004 or 2024, and only the physical condition of the unit tells you which. Always cross-check a decoded date against the rating plate and the unit itself.
Not professional advice
Nothing on this site is professional plumbing, HVAC, or safety advice. Decisions about repairing, replacing, or continuing to run a water heater — especially one that is old, leaking, or showing signs of failure — should be made with a licensed plumber who can inspect the unit in person. Do not rely on this site to judge whether a water heater is safe to operate.
No warranty
The site and its content are provided "as is", without any warranty of accuracy, completeness, or fitness for a particular purpose. We do our best to keep the decoding logic and brand information correct, but we do not guarantee it.
Trademarks
Rheem, A.O. Smith, Bradford White, Navien, Rinnai, Bosch, and all other brand and product names mentioned on this site are trademarks of their respective owners. TankBirthday is not affiliated with, endorsed by, or sponsored by any manufacturer. Brand names are used only to identify which serial formats the tools decode.
Limitation of liability
To the fullest extent permitted by law, TankBirthday and its operator are not liable for any damages — including property damage, water damage, or costs of repair or replacement — arising from your use of the site or reliance on its results.
Changes
These terms may be updated from time to time. The current version is always on this page, with its effective date shown above.