The Town of Merrimack’s Building Department, the building and code enforcement division of Merrimack Fire and Rescue at its headquarters at 432 Daniel Webster Highway, issues permits for a Hillsborough County town of around 30,000 between Nashua and Manchester — the municipality that added more residents than any other in New Hampshire over the last five years, a growth rate that shows up directly in the department’s workload. The office runs from eight to four on weekdays (603-420-1730) and takes applications through the town’s OpenGov portal. Zoning, subdivision and site plan sit with Community Development at Town Hall on Baboosic Lake Road, on a separate line.
The name needs disambiguating twice over. The Town of Merrimack is in Hillsborough County — Merrimack County is a separate county in the middle of the state containing the capital, and a search or a filing that conflates the two lands in the wrong place entirely. The Merrimack River, meanwhile, runs along the town’s eastern edge and through Manchester, Nashua and Concord. When describing a property here, the county and the river both need naming explicitly.
This guide covers the Town of Merrimack in Hillsborough County, New Hampshire. Nashua, Bedford, Amherst, Hollis and Litchfield are separate municipalities with their own building officials; Merrimack County is a different county elsewhere in the state; and no New Hampshire county issues building permits in practice.
The town is in Hillsborough County, not Merrimack County. The Town of Merrimack sits in Hillsborough County. Merrimack County is a separate county in the centre of the state, containing the capital and 26 other municipalities. A title search, a permit enquiry or a contractor's registration directed at the county of that name will not reach this town, and the confusion is common enough to be worth ruling out in the first sentence of any file.
What requires a building permit in Merrimack?
In Merrimack the questions are whether the municipality enforces, what it has amended, and the town and county that share a name, and the split between the building division at Fire and Rescue Headquarters and the zoning office at Town Hall.
Short on time to read all of this?
Get a free quote →Typically permit required
- Construction, alteration, addition, demolition and change of occupancy, on a permit before work begins
- Electrical, plumbing and mechanical work, each on its own permit by a state-licensed tradesperson
- The state's shoreland or wetlands approval on the river and pond frontage, before the local permit
- New construction and renovation, on a permit obtained before work begins under RSA 155-A:4
- Alteration, renovation, rehabilitation, repair, removal and demolition of buildings previously erected
- Electrical, plumbing and gas work, by tradespeople licensed by the state
Often exempt
- Ordinary repairs that do not alter structure, egress, fire protection or building systems
- Painting, papering, flooring, cabinets and similar finish work
- Ordinary repairs that do not alter structure, egress, fire protection or building systems
- A tent of any size erected as an accessory structure at an owner-occupied one- or two-family dwelling
- Painting, papering, flooring, cabinets and similar finish work
What the municipality may change, and what it may not
Locally, what stands out is the town and county sharing a name, the split between the building division at Fire and Rescue Headquarters on the highway and Community Development at Town Hall, and the river frontage along the eastern edge.
Every building in New Hampshire must meet the state building and fire codes (the 2024 codes since July 2026). Only towns that have adopted an enforcement mechanism issue local permits, and any local amendment must be administrative and confirmed by the state. New Hampshire rules
Who handles permitting in Merrimack?
The Building Department, part of Merrimack Fire and Rescue, is the permitting authority inside the town, administering the New Hampshire State Building Code through the enforcement mechanism Merrimack has adopted; it also carries out code enforcement, and the Fire Department issues the certificate of occupancy. Community Development at Town Hall administers the zoning ordinance and subdivision and site plan review. The State Fire Marshal permits state, university and community college buildings, the environmental department issues shoreland, wetlands and sewage approvals, and the Office of Professional Licensure and Certification licenses electricians, plumbers and gas fitters statewide.
Not sure this scope needs a permit?
Get a free quote →| Detail | Information |
|---|---|
| Department | Merrimack Building Department |
| Office | 432 Daniel Webster Highway, Merrimack, NH 03054 |
| Phone | (603) 420-1730 |
| Zoning and planning | Community Development, Town Hall, 6 Baboosic Lake Road, (603) 424-3531 |
| County | Hillsborough County — not Merrimack County |
| Hours | Monday to Friday, 8:00 am to 4:00 pm |
Permit types
Residential permits
A Merrimack house project files with the Building Department on the highway rather than at Town Hall, with the trades on their own permits and New Hampshire licences on the tradespeople. The town's rapid growth means a good deal of the residential file is new subdivision work rather than renovation, which shifts the questions towards access, drainage and the state's wetlands approvals earlier in the process than an older town would require.
Commercial permits
Commercial work in Merrimack — the highway corridor, the industrial and distribution parcels near the turnpike, the brewery and the office parks — runs through the same department with the state fire code alongside. The town's position between the state's two largest cities has made it a distribution and light industrial market, and those larger buildings reach the State Fire Marshal's pre-construction review list.
The state permits that sit outside the town
In Merrimack the Merrimack River along the eastern edge and the ponds and wetlands inland bring the state environmental department's approvals ahead of the local permit, and the rapid subdivision growth puts access and drainage at the front of most new residential files.
New Hampshire has no general contractor licence; the contractor carries the duty to meet the state codes, and the trades hold state licences. New Hampshire rules
Rather talk it over?
Call 1-855-478-4290 →Merrimack permit costs and fees
Merrimack charges building and trade permit fees under the town's schedule, with the state's own approvals charged by the department issuing them and board fees where the project reaches planning or zoning.
| Item | Fee or rule |
|---|---|
| Building permit | On the declared construction value, per the town's schedule |
| Trade permits | Separate electrical, plumbing and mechanical fees |
| State permits | Shoreland, wetlands and sewage approvals through the environmental department |
| Planning and zoning | Board application fees where the project reaches them |
| Fire review | State fire code review where the project reaches the pre-construction list |
| Trade licences | New Hampshire licences through the state licensing office |
Growth has moved the questions earlier. Merrimack added more residents than any other New Hampshire municipality over the last five years. On a new subdivision the deciding questions — access, drainage and the state's wetlands approval — arrive well before the building permit, and a programme built around the permit date rather than the approval dates will slip. Sequence the state approvals first.
Trade permits and who may pull them
Permit required
- Electrical — by an electrician licensed by the state electricians' board
- Plumbing — by a plumber licensed by the state mechanical licensing board
- Gas fitting — by a gas fitter licensed by the state mechanical licensing board
- Fire protection — under the state fire code, with the fire marshal's review where it applies
Typically exempt
- Arc-fault protection beyond the 2014 electrical requirements, which is not enforced in New Hampshire
- Like-for-like replacement the adopted code places below the permit threshold
Rather not deal with the building department?
Get a free quote →Trade work follows the town’s permit process where the town enforces, and is done by tradespeople holding the state licence their trade requires. New Hampshire rules
How to apply for a Merrimack building permit
Permitting exists locally only where an enforcement mechanism has been adopted under RSA 155-A:3; the code applies either way.
A local amendment may cover only administrative matters, is unenforceable unless the Building Code Review Board has confirmed it, and the board publishes what it confirms.
Shoreland, wetlands and subsurface sewage approvals come from the environmental department, not from the town.
Electricians, plumbers and gas fitters are licensed by the state; there is no general contractor licence, and the contractor carries the compliance duty.
The code in effect when the application is received governs the whole of the work; during a concurrency period elect one edition, not a blend.
Footing to final, with trade inspections as the town requires, then the certificate of occupancy where the town issues one.
Review, corrections and what actually causes delay
The Building Department reviews for the state building code with the state fire code alongside, and the town's planning and zoning boards take subdivision and site plan review before the permit. What delays a Merrimack project is a filing sent to Town Hall instead of the highway office, a confusion between the town and the county of the same name, and a wetlands approval left until after the design.
Want this handled start to finish?
Get a free quote →Inspections in Merrimack
Where the municipality enforces, inspections follow the code's sequence — footing, foundation, framing, rough trades, insulation and final — requested from the building official by permit number, with the trades inspected on their own permits and a certificate of occupancy at the end. Where the State Building Permit Program covers the work instead, inspections are booked with the State Fire Marshal's office at least 48 hours ahead, non-compliant work draws a written order to correct, and the re-inspection carries its own fee. Merrimack inspections are requested from the Building Department by email, 24 to 48 hours ahead, and typically run between half past nine and three on weekdays, with each trade inspected on its own permit and the certificate of occupancy at the close.
Merrimack permit search and official resources
- New Hampshire State Building Code — the adopted editions and the statewide amendments
- RSA chapter 155-A — the statute on the code, permits, enforcement and appeals
- State Building Permit Program — the fire marshal's permitting and pre-construction review
- New Hampshire State Building Code — the adopted editions, the amendments and RSA 155-A
- State Building Permit Program — the fire marshal's permits, inspections and certificates where a municipality does not enforce
- RSA chapter 155-A — the statute on the code, permits, enforcement and appeals
Inspections are where schedules slip.
Get a free quote →Frequently asked questions
Is Merrimack in Merrimack County?
No. The Town of Merrimack is in Hillsborough County. Merrimack County is a separate county in the centre of the state, containing the capital.
Who issues building permits in Merrimack?
The town’s Building Department, part of Merrimack Fire and Rescue, at 432 Daniel Webster Highway (603-420-1730), through the OpenGov portal. No New Hampshire county issues building permits in practice.
Which code applies?
The New Hampshire State Building Code — the 2024 international codes with the 2018 energy code and the 2023 electrical code, in force since the first of July 2026.
Who approves work near the river or a wetland?
The state environmental department, through the shoreland and wetlands approvals. Those come before the local building permit.
Do I need a licensed contractor?
New Hampshire issues no general contractor licence, but electricians, plumbers and gas fitters hold state licences and the contractor carries the compliance duty by statute.
Where do I file, Town Hall or the highway office?
Building permits go to the Building Department at Fire and Rescue Headquarters, 432 Daniel Webster Highway, which also handles code enforcement. Zoning, subdivision and site plan questions go to Community Development at Town Hall, 6 Baboosic Lake Road, on (603) 424-3531.
Simplify Merrimack permitting with Alliance Permitting
Merrimack is a town, a river and a county, and only one of them takes your permit. We file at the right office, name the right county, and sequence the state approvals ahead of the build.
Ready to break ground in Merrimack sooner?
Send us the scope and the parcel. We confirm the review path with the Merrimack Building Department, assemble the submittal, file it, and track it through issuance — corrections included.
More New Hampshire permitting guides
More New Hampshire permitting guides
This guide is provided by Alliance Permitting for general information about Merrimack permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.