Area codes in San Luis Obispo, California

San Luis Obispo, California uses 2 area codes — 805 and 820. The main San Luis Obispo area code is 805.

Area codes serving San Luis Obispo

Phone numbers in San Luis Obispo are written as ten digits — for example (805) 555-0190 — and fall in the Pacific Time zone.

How San Luis Obispo came to have 2 area codes

The original San Luis Obispo area code is 805, in service since 1957. As the area ran low on available numbers, an overlay code was added over the same region for new phone lines: 820 (2018). Existing numbers kept their original code — an overlay never forces anyone to change their number — which is why San Luis Obispo now uses all 2 codes and every local call is dialed with ten digits.

All California area codes · Is a San Luis Obispo call a scam?

Nearby cities

More cities in California

Frequently asked questions

What is the area code for San Luis Obispo?

The main area code for San Luis Obispo, California is 805. San Luis Obispo is now served by 2 area codes in total: 805, 820.

How many area codes does San Luis Obispo have?

San Luis Obispo has 2 area codes: 805, 820.

Why does San Luis Obispo have more than one area code?

As San Luis Obispo used up the numbers available in its original area code (805, in service since 1957), additional "overlay" codes were added over the same area so new phone numbers could keep being assigned.

How do you dial a San Luis Obispo number?

Dial all 10 digits — the area code (805 or 820) followed by the 7-digit local number. From abroad, dial +1, then the area code and number.

Sourced from the official NANPA (North American Numbering Plan Administrator) numbering database, current as of August 2, 2026. Refreshed monthly.