E.164

First published1988
Issuing bodyITU
DomainCodes and Symbols
StatusCurrent, revised 2020

About E.164

The ITU recommendation organizing the international public telephone numbering plan, first published in 1988 and absorbing the older E.163 in 1997. Country codes and a maximum of 15 digits route calls worldwide, and the plus sign prefix notation became universal.

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