Get a local business phone number in Ottawa, IL

What area code is Ottawa, IL?

Ottawa city is a Census place in LaSalle County, Illinois, with an estimated 18,775 residents in 2024. All 11 exchanges NANPA lists for its rate center are in area code 815. 815 is part of an overlay with 779, so a new local number in Ottawa may carry any of those codes depending on which have numbers available. Ottawa is in the Central time zone.

According to NANPA's dialing-plan data, local calls within 815 are dialed as 1 plus ten digits and toll calls as 1 plus ten digits.

Who holds Ottawa phone exchanges

6 carriers hold the 11 exchanges assigned to Ottawa's rate center. Level 3 Communications, LLC - Il has the most, with 3. 8 of them are pooled codes, which the holder shares with other carriers in blocks of 1,000 numbers. Holding a code means NANPA assigned that block of numbers to the carrier for this rate center; individual numbers may since have been ported elsewhere.

Local prefixes for Ottawa

These are the central office codes NANPA records for Ottawa. A caller seeing one of them recognizes a local number. The earliest assignment date recorded in the file for these codes is 2001. None were assigned in 2020 or later.

When Ottawa's exchanges were assigned

Assignment dates show when each block of Ottawa numbers was added to the local supply.

What makes a number local to Ottawa

Phone numbers are tied to a rate center, the local calling area used to decide whether a call is local or toll. Ottawa's numbers are rated to the OTTAWA rate center in NANPA's records. A business number from one of the prefixes above shows up on customers' phones as a Ottawa number.

New local numbers are drawn from carrier inventory, so the exact 815 numbers available change over time; porting an existing number is free.

Businesses around Ottawa

Ottawa is part of the Ottawa, IL micropolitan area, home to 147,000 people in 2024. County Business Patterns counted 3,355 business establishments in the Ottawa, IL micropolitan area in 2023, employing 44,039 people. The largest sectors by establishment count are retail trade (486), accommodation and food services (429), and other services (except public administration) (403).

A Ottawa number on Callata

Callata is a business phone system priced at $99 a month with 5 users included, then $20 per additional user. Callata Office includes up to 3 local business numbers, unlimited inbound calling, 1,500 pooled outbound US and Canada minutes per user each month, a browser softphone that can also ring your cell, voicemail with transcription, call recording with AI summaries, business-hours routing and E911 on every number.

If you already have a number in Ottawa, porting it to Callata is free. Texting from a local number requires a one-time carrier registration (10DLC, $49), and the numbers available in any area code depend on carrier inventory when you choose them.

Optional AI agents (receptionist, sales, support or scheduler) can answer calls after hours or when nobody picks up, take messages, text, email and transfer to your team. They are billed from prepaid AI minutes at $0.25 per minute, identify themselves as AI, and may only place outbound calls to people who consented, between 8am and 9pm.

Per-seat phone plans multiply by headcount. For the rounded average establishment size in the Ottawa, IL micropolitan area, 13 users on RingCentral RingEX Core come to $390.00 a month and on Ooma Office Pro $324.35, at month-to-month list prices checked September 28, 2026. On Callata the same 13 people cost $259.00 a month, less than either per-seat plan.