Question 1

What is the area code for Ontario?

Accepted Answer

The main area code for Ontario, California is 909. Ontario is now served by 2 area codes in total: 909, 840.

Question 2

How many area codes does Ontario have?

Accepted Answer

Ontario has 2 area codes: 909, 840.

Question 3

Why does Ontario have more than one area code?

Accepted Answer

As Ontario used up the numbers available in its original area code (909, in service since 1992), additional "overlay" codes were added over the same area so new phone numbers could keep being assigned.

Question 4

How do you dial a Ontario number?

Accepted Answer

Dial all 10 digits — the area code (909 or 840) followed by the 7-digit local number. From abroad, dial +1, then the area code and number.

Area codes in Ontario, California

Area codes serving Ontario

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