Glasgow uses UK telephone area code 0141, or +44 141 in international format.

A number beginning with 0141 814 is most likely a BT landline in Erskine, but with number portability any specific 0141 number could be located anywhere in the Glasgow area, served by any local phone company.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)