https://en.wikipedia.org/wiki/Telephone_numbers_in_estonia
Landline phone numbers have 7 digits, mobile numbers can have either 7 or 8 digits, machine-to-machine (M2M) numbers can be up to 12 digits. Telephone numbers are portable between locations and operators. The country code for Estonia is +372, adopted in 1993. This replaced the +7 014 area code, used under Soviet rule.