CallataGuidesGet a local business phone number in Durham, NH
Durham's area code, prefixes and carriers from NANPA records, and how to put a Durham number in front of your customers.
- Area code
- 603
- Exchanges
- 7NANPA-assigned
- Carriers
- 5
- Population
- 15,270Census 2024 est.
Area codes in Durham
With 15,270 residents in the Census 2024 estimate, Durham sits in Strafford County, New Hampshire. All 7 exchanges NANPA lists for its rate center are in area code 603. Durham is in the Eastern time zone.
According to NANPA's dialing-plan data, local calls within 603 are dialed as ten digits (area code plus number) and toll calls as ten digits (area code plus number).
| Area code | Exchanges here | Share | In service since | Overlay with | Time zone |
|---|---|---|---|---|---|
| 603 | 7 | 100% | 1947 | none | Eastern |
Source: NANPA utilized central office code file and NPA report, dated 10/01/2026.
Phone carriers in Durham
5 carriers hold the 7 exchanges assigned to Durham's rate center. Paetec Itel, LLC has the most, with 3. 4 of them are pooled codes, which the holder shares with other carriers in blocks of 1,000 numbers. A business number in Durham can come from any of these blocks; once it is yours, porting lets it move between providers.
| Carrier (NANPA operating company) | Exchanges | Share |
|---|---|---|
| Paetec Itel, LLC | 3 | 43% |
| Comcast Ip Phone, LLC | 1 | 14% |
| Freedom Ring Communications, LLC | 1 | 14% |
| Teleport Communications America, LLC - NH | 1 | 14% |
| Consolidated Comm of No. New England-nh | 1 | 14% |
Carrier names are the operating company (OCN) names on NANPA's utilized central office code file dated 10/01/2026. A carrier holding a code may port numbers to other carriers.
Exchanges (NPA-NXX) assigned in Durham
Each prefix below is a block of up to 10,000 numbers that NANPA assigned to Durham's rate center (DURHAM). The earliest assignment date recorded in the file for these codes is 2001. None were assigned in 2020 or later.
| Area code | Prefixes (NXX) |
|---|---|
| 603 | 295, 389, 397, 590, 815, 862, 868 |
Source: NANPA utilized central office code file.
Rate centers and local calling in Durham
Phone numbers are tied to a rate center, the local calling area used to decide whether a call is local or toll. Durham's numbers are rated to the DURHAM rate center in NANPA's records. A business number from one of the prefixes above shows up on customers' phones as a Durham number.
New local numbers are drawn from carrier inventory, so the exact 603 numbers available change over time; porting an existing number is free.
Who does business near Durham
Durham is part of the Boston-Cambridge-Newton, MA-NH metro area, home to 5.0 million people in 2024. County Business Patterns counted 133,807 business establishments in the Boston, MA-NH metro area in 2023, employing 2,681,704 people. The largest sectors by establishment count are professional, scientific, and technical services (17,803), retail trade (15,568), and health care and social assistance (15,127).
| Industry | Establishments | Employees | Employees per establishment |
|---|---|---|---|
| Full-service restaurants | 4,652 | 104,689 | 22.5 |
| Limited-service restaurants | 3,920 | 51,825 | 13.2 |
| Residential remodelers | 3,263 | 11,112 | 3.4 |
| Law offices | 2,967 | 24,707 | 8.3 |
| Landscaping services | 2,876 | 12,494 | 4.3 |
| Dental offices | 2,419 | 19,313 | 8.0 |
| Plumbing, heating and air-conditioning contractors | 2,169 | 22,860 | 10.5 |
| Beauty salons | 2,025 | 10,995 | 5.4 |
Selected small-business industries (six-digit NAICS) covered by these guides. Source: Census County Business Patterns 2023.
Setting up a Durham business line
Callata Office costs $99 per month for up to 5 people, and each additional user is $20 a month. That covers up to 3 local numbers, calling from a browser or your cell, transcribed voicemail, recorded calls with AI summaries, after-hours routing and E911 on each number.
If you already have a number in Durham, 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.
A 20-person team is the benchmark here, the rounded average establishment size in the Boston, MA-NH metro area. Billed per seat at month-to-month list prices (checked September 28, 2026), RingCentral RingEX Core costs $600.00 a month and Ooma Office Pro $499.00. On Callata the same 20 people cost $399.00 a month, less than either per-seat plan.
| Provider (plan) | Pricing basis | Per month | Per year |
|---|---|---|---|
| Callata (Callata Office) | $99 incl. 5 users, $20 per extra user | $399.00 | $4,788.00 |
| Quo (Starter) | $19.00 per user | $380.00 | $4,560.00 |
| Nextiva (Core) | $23.00 per user | $460.00 | $5,520.00 |
| Ooma (Office Pro) | $24.95 per user | $499.00 | $5,988.00 |
| Dialpad (Standard) | $27.00 per user | $540.00 | $6,480.00 |
| RingCentral (RingEX Core) | $30.00 per user | $600.00 | $7,200.00 |
Competitor prices are each vendor's published month-to-month list price per user for its lowest plan that includes business calling and texting, checked September 28, 2026: Quo Starter $19, Nextiva Core $23, Ooma Office Pro $24.95 (Essentials excludes texting; one-time $29.95 activation not included), Dialpad Standard $27, RingCentral RingEX Core $30 ($20 billed annually). Prices exclude taxes and fees and may change; annual contracts lower some competitors' prices.
Frequently asked questions
What area code is Durham, NH?
603. All exchanges NANPA lists for Durham are in 603.
How many phone companies have exchanges in Durham?
5, holding 7 exchanges between them, according to NANPA's 10/01/2026 file.
Can I keep my existing Durham business number?
Yes. Porting an existing number to Callata is free. Texting from it starts after carrier registration (10DLC), a one-time $49 fee.
How much is a business phone line in Durham?
Callata is $99 a month with 5 users included, then $20 per additional user, with up to 3 local numbers; 20 users come to $399.00 a month. For comparison, 20 users on RingCentral RingEX Core list at $600.00 a month (checked September 28, 2026).