How Old Is Your Maytag Water Heater?
Maytag water heaters were built by State Industries — the company that became part of A.O. Smith in 2001 — so they carry State's serial number format rather than the date codes used on Maytag washers and dryers. The manufacture date is encoded in the first characters of the serial, and dating one takes seconds once you know the pattern. Enter your serial number in the free decoder above for an instant answer, or follow the guide below to read it yourself.
Since Maytag hasn't sold water heaters for years, every unit you'll encounter is an older one.
Where to Find the Serial Number
Check the rating plate (data plate) on the side of the tank — a silver or white sticker, usually in the upper half, that lists the model and serial numbers together. The serial is typically 10–12 characters long and starts with one or two letters.
Serials on older units can fade or get painted over. If yours is hard to read, take a photo and bump the contrast — you only need the first few characters to get the date.
How the Maytag Serial Format Works
The date code is a month letter followed by a two-digit year. Month letters run A through M, skipping I (A = January, B = February … M = December).
Worked example — L07A0811460:
L= November (the 11th month letter, A–M skipping I)07= 2007 (year)- The remaining characters = factory and production sequence
- Result: manufactured in November 2007
Watch for a leading factory letter. Some serials carry an extra letter in front of the date block. Skip it and read the next letter plus two digits. For example, D03108164 decodes to April (D) 2003.
Because the year is only two digits, a serial like ...03 could in theory mean 2003 or earlier — but since Maytag water heaters were only sold from the late 1990s onward, the 2000s reading is almost always right.
Why Your Maytag Water Heater's Age Matters
- Lifespan. Tank water heaters average 8–12 years of service. Every Maytag unit is already well beyond that, so internal corrosion — and the risk of a flooded floor — rises every year it stays in service.
- Replacement planning. With the brand discontinued and every unit past its design life, proactive replacement beats emergency repair — knowing the exact date helps you plan calmly.
- Home sales and insurance. Buyers, inspectors, and insurers often ask for a water heater's age. A decoded serial gives you a documented answer instead of a guess.
Sources
Manufacture by State Industries confirmed by How To Look At A House's Maytag water heater dating guide and the Building Intelligence Center's Maytag serial number styles. State Industries' place in the A.O. Smith family is documented on State's product cross-reference page, and the letter-month coding is cross-checked against the InterNACHI water heater dating chart.