What are the syntax restrictions on a .tel domain?
The minimum number of characters in a .tel domain is 3 and the maximum number is 63 not including the .tel suffix. Every domain must contain at least one letter from a-z or “A to Z” in standard US ASCII script. No domain can begin or end with a hyphen nor can a domain have a hyphen in the 3rd and 4th position. A .tel domain may not consist purely of digits. The .tel naming conventions are described in detail in the Acceptable Use Policy. The reserved list is also available for review.