RFC 3966: The tel URI for Telephone Numbers

Publisher

IETF / RFC Editor

URL

https://www.rfc-editor.org/rfc/rfc3966.html

Published

2004-12-01

Updated

unknown

Accessed

2026-09-23

HTTP status

200

License

IETF Trust; RFC text may be quoted with attribution; short excerpts and locators only

Source notes citing this source

• In a tel URI a global number is identified by a leading '+' and must consist of the E.164 country code and national number. in context
• A local number in a tel URI must carry a phone-context parameter identifying the scope in which it is valid. in context
• In the tel URI standard, globally unique numbers are identified by a leading + and are composed of the country code and national significant number per E.123 and E.164. in context
• The phone-context value of a local tel URI is a domain name or a global number prefix, and it is not a prefix that can be prepended to turn the local number into an E.164 number. in context
• The tel URI defines an 'extension' parameter for extensions and an 'isdn-subaddress' parameter for ISDN subaddresses. in context
• RFC 3966 requires a tel URI global number to consist of the country code and the national significant number, as specified in E.123 and E.164. in context
• Under RFC 3966, two tel URIs can be equivalent only if both are global numbers or both are local numbers, so a global number never equals a local number. in context
• In a tel URI, a global number is identified by a leading '+' character. in context
• A tel URI local number must carry a phone-context parameter that identifies the scope in which it is valid. in context
• RFC 3966, which defines the tel URI, is a Standards Track document published in December 2004 that obsoletes RFC 2806. in context
• Visual separators in a tel URI, such as hyphens, dots and parentheses, are for readability only and are not used for URI comparison or for placing the call. in context

Cite this source record

APA

WarmTransfer. (2004, December 1). RFC 3966: The tel URI for Telephone Numbers. WarmTransfer. https://warmtransfer.net/knowledge/sources/rfc-3966-tel-uri-b

BibTeX

@misc{warmtransfer-rfc-3966-tel-uri-b,
  title  = {RFC 3966: The tel URI for Telephone Numbers},
  author = {{WarmTransfer}},
  year   = {2004},
  url    = {https://warmtransfer.net/knowledge/sources/rfc-3966-tel-uri-b},
  note   = {IETF / RFC Editor, accessed 2026-09-23}
}