What does plus 44 mean in a telephone number?

+44 is the country code for the UK when displaying telephone numbers in international format. The plus sign means "insert your international access prefix here"; the most common prefix is 00, but many countries use other prefixes. You also must omit the trunk prefix 0 from the UK domestic number when changing it to international format.

For example, mobile code 07412 becomes +44 7412.

It is incorrect to try to make a hybrid format, as, for example, +44 (0) 7412. A telephone number in international format should have only the single plus sign, digits, and blank spaces to separate groups of digits. No other punctuation is allowed.

(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.)

+44 is the international dialling code for the United Kingdom (UK).

Within the UK, area dialling codes start with a zero - for example mine is 01332 which is then followed by the personal number, mostly 6 digits in the UK but larger UK cities have 7 digits, and a few cities have 8 digits.

In UK, if we want to connect to another phone with the same dialling code, we only have to dial the personal number (5 to 8 digits).

If we want to connect to a phone elsewhere in the Country we dial the area code followed by the personal number.

If we are in another ccountry, for example France and wanted to call someone in the UK, we would need to dial +44 instead of the first zero of the dialling code, then the remaining digits of the dialling code, followed by the personal number.