CallataGuidesGet a local business phone number in Merrimack, NH
Merrimack's area code, prefixes and carriers from NANPA records, and how to put a Merrimack number in front of your customers.
- Area code
- 603
- Exchanges
- 23NANPA-assigned
- Carriers
- 8
- Population
- 29,367Census 2024 est.
Merrimack area codes
Merrimack town is a Census town in Hillsborough County, New Hampshire, with an estimated 29,367 residents in 2024. All 23 exchanges NANPA lists for its rate center are in area code 603. Merrimack 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 | 23 | 100% | 1947 | none | Eastern |
Source: NANPA utilized central office code file and NPA report, dated 10/01/2026.
Phone carriers in Merrimack
8 carriers hold the 23 exchanges assigned to Merrimack's rate center. United States Cellular - NH has the most, with 7. 17 of them are pooled codes, which the holder shares with other carriers in blocks of 1,000 numbers. The table counts codes by the operating company NANPA assigned them to, not by who serves each number today.
| Carrier (NANPA operating company) | Exchanges | Share |
|---|---|---|
| United States Cellular - NH | 7 | 30% |
| Consolidated Comm of No. New England-nh | 6 | 26% |
| Omnipoint Miami E License, LLC | 3 | 13% |
| Bell Atlantic Mobile, INC | 2 | 8.7% |
| Paetec Itel, LLC | 2 | 8.7% |
| Mcimetro Access Transmission Services LLC - NH | 1 | 4.3% |
| American Messaging Services, LLC | 1 | 4.3% |
| Metropcs, INC. | 1 | 4.3% |
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 Merrimack
These are the central office codes NANPA records for Merrimack. 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.
| Area code | Prefixes (NXX) |
|---|---|
| 603 | 261, 262, 341, 345, 365, 377, 396, 420, 423, 424, 429, 440, 461, 493, 494, 517, 533, 582, 620, 670, 683, 820, 913 |
Source: NANPA utilized central office code file.
How local numbers work in Merrimack
What a caller sees as "local" is the area code plus prefix. In Merrimack, those come from the MERRIMACK rate center, as recorded by NANPA.
New local numbers are drawn from carrier inventory, so the exact 603 numbers available change over time; porting an existing number is free.
The local business market
Merrimack is part of the Manchester-Nashua, NH metro area, home to 430,000 people in 2024. County Business Patterns counted 11,028 business establishments in the Manchester, NH metro area in 2023, employing 186,868 people. The largest sectors by establishment count are retail trade (1,488), construction (1,383), and professional, scientific, and technical services (1,202).
| Industry | Establishments | Employees | Employees per establishment |
|---|---|---|---|
| Full-service restaurants | 365 | 8,223 | 22.5 |
| Limited-service restaurants | 305 | 4,771 | 15.6 |
| Landscaping services | 245 | 1,193 | 4.9 |
| Physician practices | 228 | 3,772 | 16.5 |
| Residential remodelers | 217 | 564 | 2.6 |
| Plumbing, heating and air-conditioning contractors | 206 | 1,988 | 9.7 |
| Dental offices | 198 | 1,778 | 9.0 |
| Law offices | 194 | 1,462 | 7.5 |
Selected small-business industries (six-digit NAICS) covered by these guides. Source: Census County Business Patterns 2023.
Setting up a Merrimack 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 Merrimack, 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 Manchester, NH metro area, 17 users on RingCentral RingEX Core come to $510.00 a month and on Ooma Office Pro $424.15, at month-to-month list prices checked September 28, 2026. On Callata the same 17 people cost $339.00 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 | $339.00 | $4,068.00 |
| Quo (Starter) | $19.00 per user | $323.00 | $3,876.00 |
| Nextiva (Core) | $23.00 per user | $391.00 | $4,692.00 |
| Ooma (Office Pro) | $24.95 per user | $424.15 | $5,089.80 |
| Dialpad (Standard) | $27.00 per user | $459.00 | $5,508.00 |
| RingCentral (RingEX Core) | $30.00 per user | $510.00 | $6,120.00 |
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 Merrimack, NH?
603. All exchanges NANPA lists for Merrimack are in 603.
How many phone companies have exchanges in Merrimack?
8, holding 23 exchanges between them, according to NANPA's 10/01/2026 file.
Can I keep my existing Merrimack 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 Merrimack?
Callata is $99 a month with 5 users included, then $20 per additional user, with up to 3 local numbers; 17 users come to $339.00 a month. For comparison, 17 users on RingCentral RingEX Core list at $510.00 a month (checked September 28, 2026).