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Short number

published · September 27, 2026

A short number is a service code dialled or texted inside one country, such as 911, 311 or an SMS short code. It has no international form, and Spaw answers it invalid and free.

A short number is a service code dialled or texted inside one country, shorter than a subscriber number and with no international form: an emergency number such as 911 or 112, a service code such as 311, a directory or helpline number, or the codes businesses send text messages from. It reaches a service rather than a subscriber, and it means something only inside the country whose plan defines it; the same digits can be another service, or nothing, elsewhere.

In North America the three-digit N11 codes are the best-known set. NANPA lists 211 for community information and referral, 311 for non-emergency police and other government services, 411 for local directory assistance, 511 for traffic and transportation information (weather and traveller information in Canada), 611 for repair service, 711 for the telecommunications relay service, 811 for the one-call service before digging (a non-urgent health line in Canada) and 911 for emergencies. In the US the FCC administers them and recognises 211, 311, 511, 711, 811 and 911 as nationally assigned (https://www.nanpa.com/numbering/abbreviated-codes, accessed 27 September 2026).

What Spaw answers

A short number is not a subscriber number, so the answer is valid: false with the reason short_number, or emergency_number for a code the country's metadata lists as an emergency number, with the number's fields null and blocked_by: invalid. Invalid answers are free, and neither reason ever carries a did_you_mean suggestion. Both are read from libphonenumber's short-number metadata for the country sent, so the lookup needs one: with country: "US", 911 and 112 answer emergency_number and 211, 311, 411 and 611 answer short_number; with "GB", 999 and 112 answer emergency_number and 101 and 111 answer short_number. The US metadata (libphonenumber 9.0.37) accepts any four- to six-digit code starting with 2 to 9 as a short number, so an SMS short code sent with country: "US" answers short_number too.

What it does not mean

short_number says the digits are a short code in that country's plan, not that a service answers on them today or who runs it. Without a country, digits this short answer missing_country, because a short number has no calling code to be read from, and written with one (+1 911) they are simply too_short. A short number never has an E.164 form, so there is nothing to store for it as a contact number. Which numbers a country's plan treats as subscriber numbers, with an example of each type, is on its page under phone facts by country.

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More glossary

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