Heathrow uses the London area code, which is 020.
A typical London number follows the pattern (020) xxxx xxxx. As an example, the number 020 7222 1234 would be dialled as follows:
From another London 020 landline phone:
7222 1234
From a phone elsewhere in the UK or a mobile phone:
020 7222 1234
From outside the country:
+44 20 7222 1234
(where + represents the international access code used by the country being called from, usually 00 or 011)
0121 serves the Birmingham, England area for telephone networks.
(01933) or +44 1933.
01420 is for Alton, in Hampshire.
01274 +44 1274 from overseas.
Chipping Norton, Oxfordshire.
The area code of 01702 is for the seaside resort of Southend-on-Sea.
It is (01603) or +44 1603.
It is (01433), or +44 1433 from overseas. Hope that helps! ^ - ^
There is no telephone area code 185 in Russia.
Area code 0191 is "Tyne and Wear" in the north of England, and a number beginning with 0191 3 is in Durham.
Redruth is in area code 01209. From outside the UK, this is dialled as +44 1209 (where "+" means your country's international access code)
The code 116 is not used in the US to localise a particular area and is instead used in the United Kingdom to localise a telephone number to a part of Leicester in England.