Sources
We list the organisation, the type of source and the date we last opened and checked it. Where a source is a third-party technical reference rather than the manufacturer, we say so — that affects how much weight the rule carries, and we would rather you could see it than have to take our word for it.
All sources
GE Appliance — How to Determine the Age or Manufacture Date
Official manufacturer documentationGE Appliances (Haier) · last checked 29 July 2026
Manufacturer support article giving the month-letter table, the year-letter table and the statement that the year letter rotates approximately every 12 years.
Used by: ge-two-letter-month-year, hotpoint-us-ge-system, kenmore-ge-built
Monogram Appliance — How to Determine the Age or Manufacture Date
Official manufacturer documentationGE Appliances (Haier) · last checked 29 July 2026
Confirms the same two-letter date code is used across GE's premium brands.
Used by: ge-two-letter-month-year
Sears and Kenmore Appliance Model Prefix Chart
Manufacturer-authorised parts or service documentationPartSelect · last checked 29 July 2026
Parts retailer chart corroborating the Kenmore manufacturer prefix mapping.
Used by: kenmore-whirlpool-built, kenmore-ge-built, kenmore-frigidaire-built
Sears Appliance Manufacturing Codes
Established appliance repair organisationAppliance Aid · last checked 29 July 2026
Long-standing appliance repair reference listing the three-digit Kenmore model prefixes and the manufacturer each maps to, including Canadian C-prefixes.
Used by: kenmore-whirlpool-built, kenmore-ge-built, kenmore-frigidaire-built
Who makes Sears, Kenmore appliances?
Established appliance repair organisationAppliance411 · last checked 29 July 2026
Independent repair reference corroborating that the Kenmore model prefix identifies the original equipment manufacturer.
Used by: kenmore-whirlpool-built, kenmore-ge-built, kenmore-frigidaire-built
Major Appliance Manufacturers' Date Codes
Credible technical referenceAppianceDates.com · last checked 29 July 2026
Index confirming which coding system each brand family uses, including the note that Maytag-branded appliances built after the 2006 Whirlpool acquisition moved to the Whirlpool code.
Used by: whirlpool-standard-1990, maytag-whirlpool-system-2006, maytag-legacy-24-year, kitchenaid-whirlpool-system, amana-whirlpool-system-2006, frigidaire-electrolux-system, electrolux-na-system
GE Date Codes
Credible technical referenceElectrical Forensics · last checked 29 July 2026
Forensic engineering reference reproducing GE's month and year letter tables with the 12-year cycle mapped out from 1980.
Used by: ge-two-letter-month-year, hotpoint-us-ge-system, kenmore-ge-built
Whirlpool Date Codes
Credible technical referenceElectrical Forensics · last checked 29 July 2026
Gives the character-by-character breakdown (division letter, year letter, two week digits, sequence) and both the 1970-1989 numeric table and the 1990-onwards alphanumeric table with its 20-year repeat.
Used by: whirlpool-standard-1990, maytag-whirlpool-system-2006, kitchenaid-whirlpool-system, amana-whirlpool-system-2006, kenmore-whirlpool-built
Maytag Date Codes
Credible technical referenceElectrical Forensics · last checked 29 July 2026
Reproduces the legacy Maytag year and month letter tables built from a 24-letter alphabet that omits I and O.
Used by: maytag-legacy-24-year
Electrolux Date Codes
Credible technical referenceElectrical Forensics · last checked 29 July 2026
Position-by-position breakdown of the Electrolux/Frigidaire ten-character serial, and the explicit statement that the decade digit is not encoded anywhere in the serial or model number.
Used by: frigidaire-electrolux-system, electrolux-na-system, kenmore-frigidaire-built
Bosch Date Codes
Credible technical referenceElectrical Forensics · last checked 29 July 2026
Describes the FD number as decade digit, year digit and two month digits, with the documented worked example FD9111 = November 2011.
Used by: bosch-fd-number
Bosch FD number production date decode, explained
Credible technical referenceTab-TV · last checked 29 July 2026
Independent reference corroborating the +20 year offset in the Bosch/Siemens FD number, with worked examples.
Used by: bosch-fd-number
Rules and their sources
Which sources sit behind each shipped rule.
| Rule | Manufacturer | Sources | Reviewed |
|---|---|---|---|
| whirlpool-standard-1990 | whirlpool | Electrical Forensics, AppianceDates.com | 29 July 2026 |
| maytag-whirlpool-system-2006 | maytag | Electrical Forensics, AppianceDates.com | 29 July 2026 |
| maytag-legacy-24-year | maytag | Electrical Forensics, AppianceDates.com | 29 July 2026 |
| kitchenaid-whirlpool-system | kitchenaid | Electrical Forensics, AppianceDates.com | 29 July 2026 |
| amana-whirlpool-system-2006 | amana | Electrical Forensics, AppianceDates.com | 29 July 2026 |
| ge-two-letter-month-year | ge | GE Appliances (Haier), GE Appliances (Haier), Electrical Forensics | 29 July 2026 |
| hotpoint-us-ge-system | hotpoint | GE Appliances (Haier), Electrical Forensics | 29 July 2026 |
| frigidaire-electrolux-system | frigidaire | Electrical Forensics, AppianceDates.com | 29 July 2026 |
| electrolux-na-system | electrolux | Electrical Forensics, AppianceDates.com | 29 July 2026 |
| kenmore-whirlpool-built | kenmore | Appliance Aid, Appliance411, PartSelect, Electrical Forensics | 29 July 2026 |
| kenmore-ge-built | kenmore | Appliance Aid, Appliance411, PartSelect, GE Appliances (Haier), Electrical Forensics | 29 July 2026 |
| kenmore-frigidaire-built | kenmore | Appliance Aid, Appliance411, PartSelect, Electrical Forensics | 29 July 2026 |
| bosch-fd-number | bosch | Electrical Forensics, Tab-TV | 29 July 2026 |
On using third-party references
Manufacturers publish less about their date codes than you might expect. GE is the notable exception — its support site documents the two-letter system openly, including the twelve-year repeat. For most other brands, the best available documentation comes from forensic engineering references and long-established appliance repair organisations that have reproduced manufacturer service tables.
Where we rely on those, we say so in the source list and weight the rule accordingly. We corroborate across at least two independent references before shipping, and we record the date each was checked so a stale citation is visible rather than hidden.
Found something wrong?
If you know an appliance's real manufacture date and our result disagrees, that is genuinely useful information. A verified counter-example is the fastest way to get a rule corrected.