How do you read telephone numbers in the US and in the UK?

In the United States (US) people usually, read each number individually (e.g., “five-five -five”) with pauses by section (every three numbers). While in the United Kingdom (UK), people often use “double” for repeated numbers and sometimes pair up digits (e.g., “double five” for "55"). If there’s a “0” in the number, Americans (US) typically say “zero,” while British English speakers often say “oh”.

For example:

US style: (415) 867-5309 would be read as "four-one-five-eight-six-seven, five-three-zero-nine."

British style: (020) 7946 0958 might be read as “oh-two -oh, seven-nine-four-six, oh-nine-five-eight.”