Water Heater Dating Chart

Please review:

Looks good but what the tank less heaters?

Bradford white is always a pain in the butt. They loop there years over and over. They also miss some of the letters. Here is a list for Bradfords that I found.

Updated… Thank you.

Greg, I have a package of door prizes coming your way.

What came first … the chicken or the egg …


Thanks Nick just here to help,

If anyone has any other updates/additions, please post them.

Giant very popular here, date on tank.

Thanks Marcel.

I just came across this while searching for info. on a Reliance WH. While is is good info, it doesn’t help me because the code I have doesn’t contain any letters.

In the 1990s for Reliance Water Heaters, **the letter before the first number is coded for the FISCAL MONTH and the first two numbers represent the FISCAL YEAR of manufacture. **The FY ran from October 1st - September 30th.

A.O. Smith acquired State Industries Inc. and subsidiary APCOM Inc. back in 2001. (IIRC it might have been May 2001).

Prior to A.O. Smith’s acquisition, the operations Fiscal Year began on October 1st and ended September 30th of the year (first two ##s). At that time they used an alpha code “A” through “M” skipping “I” as follows: “A” being the First month of the Fiscal Year (October) and the year code would be that of the fiscal (not calendar) year, that is to say the year code representing the year date for the next September 30th.

Sometime on or after the A.O. Smith acquisition they switched to a Calendar year and month date coding system.

Therefore, The Original Poster’s serial number “H92…” means that the water heater was manufactured in May during the fiscal year ending September 30, 1992 and not in August.



A = October ## is that of the fiscal year end - actual date of manufacture year is MINUS ONE from what is displayed. (for example if** A92 is displayed, was manufactured in October 91**).

B = November ## is that of the fiscal year end - actual date of manufacture year is minus one.

C = December ## is that of the fiscal year - actual date of manufacture year is minus one.

D = January ## fiscal year and actual date of manufacture year are the same.

E = February ## fiscal year and actual date of manufacture year are same.

F = March ##

G = April

H = May

J = June

K = July

L = August

M = September, fiscal year end - example M92 is September 1992.

Next fiscal year, October = A ## (plus one as for next fiscal year.A93 is october 1992.

Sometime near to the acquisition and well prior to early 2004, they changed to A = January through M = December (still skipping “I”) and using actual calendar month and year of manufacture.

Additionally, at least following the acquisition by A.O.Smith, some Reliance SNs have MORE than ONE letter. (additional A or M for example). In that event, it is the LAST letter prior to the FIRST number that indicates the month of manufacture, followed by the two digit year of manufacture.

Sources: References regarding the Iowa case Myers v Reliance Water Heater, State Industries, A.O. Smith, et al. Appeal of Summary Judgement (reversed and remanded) see link:
SCOTT MYERS, Individually, and SCOTT MYERS, as Parent as Next Friend

note references to:

Deposition of Donald J. McKeeby Jr. He has been employed by State Industries as a claims manager since 1991. McKeeby Deposition exibit:
State Industries computer printouts. One such printout shows a water heater with a serial number of “B95355638” was manufactured on “11/10/94.”

Affidavit of Steve Maxey, the national technical sales manager for State Industries, has worked for the company in various positions since 1967. Maxey’s affidavit in support of Motion for Summary Judgement.

Regarding to confirmation of additional prefix letter possible see Reliance Water Heater Recall of propane water heaters manfactured from dates in 2004 to dates in 2005 with sooting problems. Note also change in date coding system then corresponded with actual calendar month and year of manufacture (CPSC and Reliance web site - Recall Notice).

Kenmore and Maytag typically follow A.O. Smith and/or State dating codes


Yea, but that one is not EXACTLY like the one Ben posted … seems like people are snagging stuff for their own web pages right off the NACHI website … :roll:

I believe that State Industries began using an 11 digit serial number after 2008.

The first two positions are the year followed by a two digit week. The picture shows a water heater made in 16th week of 2009

Hey Ben, and everyone else. What about this one! U.S. Water Heater Company-JGR243073

Ben, may want to add U.S. Water Heater Company to the Bradford White trade names. Just got answer courtesy of:
Greg Mathias, CCHI
Journeyman Carpenter
Global Property Inspections
Lloydminster, AB. Canada
“US heating company and Bradford white are one in the same company.
July of 1992.”