REAV

Glossary

IMEI

International Mobile Equipment Identity

The fifteen-digit number that identifies a mobile device on cellular networks - distinct from the manufacturer serial number, and not interchangeable with it.

An IMEI is fifteen digits. The first eight are the Type Allocation Code, allocated under the GSMA scheme and identifying the model; the rest identify the unit, with a final check digit computed by the Luhn algorithm. A device with more than one cellular radio carries more than one IMEI.

It is not the same identifier as the manufacturer serial number, and the difference has consequences. The IMEI is what a network operator and a blocklist recognise, so it is the identifier that answers the question of whether a handset has been reported lost or stolen. The serial number is what the manufacturer recognises, so it is the one that answers warranty and part-compatibility questions.

An operation handling phones therefore needs both on the same record, captured at intake rather than reconstructed later. Checking the IMEI against a blocklist before work starts is what prevents effort being spent on a device that cannot legally be resold.

Laptops, tablets without cellular and most other equipment have no IMEI at all, which is why a device record has to accommodate several identifier types rather than assume one.

One record per device, whatever identifies it

Related terms

  • Chain of custody The unbroken, documented record of who held a device, when, and what was done to it, from collection to final disposition.
  • Triage The intake decision that routes each incoming device toward repair, parts harvesting, direct resale or recycling.
  • Device grading The standardised assessment that assigns a used device a cosmetic and functional condition, driving its price and its route through the workshop.
  • ITAD The controlled process of retiring IT equipment so that data is destroyed, value is recovered and disposal is documented.

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