Whirlpool serial numbers are either 9 or 10 characters. On 9-digit serials the 2nd character is the year letter and characters 3–4 are the week. On 10-digit serials, the year letter shifts to the 3rd position and the week to characters 4–5. The same letter repeats every 12 years (e.g., M = 1983, 1995, 2007, 2019), so decade context matters. This rule covers Whirlpool, Maytag (post-2006), KitchenAid, Roper, Estate, Inglis, and most Kenmore.
What a Whirlpool Serial Number Actually Encodes
A Whirlpool serial number encodes four things: a division/factory code, a year letter, a production week, and a sequential unit number. The division code identifies which Whirlpool factory or sub-brand built the unit. The year letter and week together give you the exact manufacturing date to within seven days.
Unlike GE (which puts month before year), Whirlpool uses week not month — so a Whirlpool serial decoded as "2019 / week 14" means the third week of April 2019.
The 9-Digit vs 10-Digit Rule (Critical)
Most online guides conflate these two formats, producing wrong results for a significant share of Whirlpool appliances. The rule is simple:
- 9-digit serial: Position 2 = year letter · Positions 3–4 = production week
- 10-digit serial: Position 3 = year letter · Positions 4–5 = production week
To determine which format you have: count the total characters. If 9, use the first format. If 10 (more common on appliances made after ~2010), use the second.
The Whirlpool Year Letter Chart (1985–2026)
| Letter | Years | Letter | Years |
|---|---|---|---|
| E | 1987, 1999, 2011, 2023 | N | 1988, 2000, 2012, 2024 |
| F | 1989, 2001, 2013, 2025 | P | 1990, 2002, 2014, 2026 |
| G | 1991, 2003, 2015 | R | 1992, 2004, 2016 |
| H | 1993, 2005, 2017 | S | 1994, 2006, 2018 |
| J | 1995, 2007, 2019 | T | 1996, 2008, 2020 |
| K | 1996, 2008, 2020 | V | 1997, 2009, 2021 |
| L | 1998, 2010, 2022 | X | 2019, technically overlap — use model year |
Note: Letters I, O, Q, U, W, Y, Z are not used to avoid confusion. The full authoritative chart is at Lumaye Consulting and HomeSpy.
Worked Examples
Example 1 — 9-digit Kenmore dryer: Serial MB1402320
- Position 1: M = division (Whirlpool-built Kenmore)
- Position 2: B — not a standard year letter; this is an older pre-1985 unit. Cross-reference the model's design date.
- Positions 3–4: 14 = week 14
Example 2 — 10-digit Whirlpool washer WTW5000DW1: Serial C60842986X
- Position 1: C = division code (Clyde, Ohio plant)
- Position 2: 6 = not the year (this is 10-digit, so skip)
- Position 3: 0 — year letter. "0" is not in the letter set, meaning this is actually an 11-character anomaly; recount.
Example 3 — 10-digit Maytag dryer (post-2006 Whirlpool scheme): Serial MX06404786
- Positions 1–2: MX = division (Maytag/Clyde)
- Position 3: 0 — cross-check: year letter for 2020 is X; but position 3 here is "0". Count again carefully — Maytag post-2006 uses the 10-digit scheme with letter at position 3.
- Correct read: Position 3 = X = 2020; Positions 4–5 = 06 = week 6 (first week of February 2020).
Brands That Use the Whirlpool Scheme
All of the following brands have used or currently use the Whirlpool serial encoding system: Whirlpool, Maytag (post-2006), Amana, KitchenAid, Roper, Estate, Inglis, Jenn-Air (post-2006), Admiral, and most Kenmore (Kenmore units manufactured by Whirlpool — check the 3-digit prefix: 110 = Whirlpool-made).
Important: Maytag appliances made before 2006 use a completely different encoding scheme and the Whirlpool rules do not apply.
Common Decoding Mistakes
- Treating a 10-digit as 9-digit: The most common error. Always count characters first.
- Ignoring the division code: The first character (or first two on some 10-digit) is not part of the year/week.
- Assuming pre-2006 Maytag = Whirlpool scheme: It doesn't. Pre-2006 Maytag used its own encoding.
- Not resolving the 12-year ambiguity: A letter like "J" could be 1995, 2007, or 2019. Cross-reference with owner's manual print date or appliance styling era.