The telephone number system conforms to international standards. Telephone numbers include the international dialling code (0084), the Lao Cai province code (20 when calling from abroad, 020 when calling from another province in Vietnam), followed by a six-digit number. For a local call, the six-digit number is enough. For a call to Hanoi, dial 0084 4 from abroad (04 from another province in Vietnam), followed by the seven-digit number.
You can place a call to a foreign country from most towns and big villages in the provinces (00 + country code + area code + telephone number). There is mobile phone coverage in and around the main towns in the provinces.