Suffolk County, New York Building Permit Guide

Suffolk County does not issue building permits. Each of the ten towns has a building department for land outside its villages, and each of the 32 incorporated villages permits construction inside its own boundaries. What the county adds is substantial: the Department of Health Services must approve the sewage system and water supply for most new or enlarged buildings, the Department of Labor, Licensing and Consumer Affairs licenses home improvement contractors and electricians and plumbers, and Public Works issues highway work permits for county roads.

What requires a building permit in Suffolk County?

The list comes from the town or village code, and the Suffolk towns write theirs in detail. The finished town guides on this site show how much they vary: Southold exempts some small alterations by cost, East Hampton spells out fence heights and small structures, and Riverhead lists its exemptions in Chapter 217. Each village applies its own code, not the town’s.

The county approvals do not replace the local permit, and a town may hold its permit until they are in hand: Southold’s application checklist, for example, asks for the SCDHS approval, and DPW warns that skipping its review of work next to a county road can affect a property’s certificate of occupancy.

What the towns and villages decide and what the state holds

The 2025 Uniform Code and Energy Code are the same in Lindenhurst as in Montauk. Town and village boards set zoning, wetlands and coastal rules, fees and local licensing; in Southold and East Hampton the town trustees also issue permits for work near the water.

Suffolk County building department: who handles permitting

Start with whether the address is inside an incorporated village; a hamlet name such as Montauk, Ronkonkoma or Mattituck is not a village, and those areas are permitted by the town. Two reservations, the Shinnecock and Poospatuck, are tribal land rather than town or village territory. Finished guides on this site cover all ten towns except Shelter Island, plus the Village of Lindenhurst.

Sag Harbor straddles the East Hampton and Southampton town line, and its Building Department covers both parts. Where the table gives only a village hall number, ask the village hall which officer handles building permits.

What Suffolk County itself does

• Department of Health Services, Office of Wastewater Management, 360 Yaphank Avenue, Suite 2C, Yaphank (631-852-5700; counter Monday to Friday 9 am to 4 pm): permits sewage disposal systems and water supply connections under Article 6 of the Sanitary Code for new homes, additions, conversions, accessory apartments, commercial buildings and subdivisions.
• Department of Labor, Licensing and Consumer Affairs, Hauppauge (631-853-4600): home improvement contractor licenses and electrician and plumber licenses under Chapter 563, with an online license search.
• Department of Public Works, Highway Permits (631-852-4100): utility, non-utility, sign and hauling permits for the county right-of-way.

Suffolk County permit types and applications

Residential permits

Most towns now take applications online (OpenGov in Babylon and East Hampton, CitySquared in Smithtown and Shelter Island, the town’s own digital services in Brookhaven), while villages range from online portals to paper forms at village hall. On the county side, the Office of Wastewater Management has separate residential forms for a new single-family house (WWM-059), additions, remodeling and conversions (WWM-057), accessory apartments (WWM-105) and extensions or transfers of an existing approval (WWM-104), each filed with its mandatory checklist and design plans.

Building or remodeling a home here? Alliance handles residential permit applications, so the crew isn't waiting on the counter.

Commercial permits

Commercial projects need the town or village site plan approval and an SCDHS application for sewage and water facilities for other than single-family homes, with four site plans by a licensed design professional and a short environmental assessment form. Projects on or next to a county road need a DPW non-utility highway work permit, and any new utility connection a separate utility permit, which the utility company applies for after the owner’s permit is in place.

For tenant improvements and new commercial builds, Alliance handles commercial building permits through issuance. More on this: commercial building permits explained.

What comes before the building permit

• Zoning and boards: zoning approval, variances, site plan and wetlands or trustee permits from the town or village.
• SCDHS sanitary approval: required for most new and expanded buildings; the county encourages a pre-application meeting.
• Innovative septic: for applications filed since July 1, 2021, a new or expanded house or a major reconstruction that uses an on-site system must install an approved innovative and alternative system (I/A OWTS), unless the parcel is in a proposed sewer district or the project meets the exemption criteria, which include not being a major reconstruction and not adding bedrooms beyond those already approved.
• County road referral: DPW needs a General Municipal Law 239-f referral from the town before it will issue a highway work permit.

Building permit fees in Suffolk County

Building permit fees are set by each town or village board, and the methods differ sharply: some charge a percentage of construction cost, others a base fee plus a rate per square foot. The table gives examples from town schedules covered in the finished guides and from Shelter Island’s building page, and how the county’s sanitary fee is charged.

Worked example: under Southold’s schedule, a 2,000 sq ft house costs $250 plus 2,000 × $0.50, a $1,250 building permit before electrical and certificate fees. SCDHS invoices its application fee only after staff accept the application into formal review.

Trade permits and who may pull them

Suffolk is one of the places in New York where licensing is done by the county. Chapter 563 of the County Code makes it unlawful to work as a home improvement contractor without a county license, and requires the license number on all advertising. Article XI of the same chapter licenses electricians and plumbers, and master and restricted electricians must complete continuing education before renewal. Some towns and villages keep licensing laws of their own as well; East Hampton, for example, issues its own home improvement license and Lindenhurst licenses plumbers. Electrical inspections are carried out by electrical inspection agencies or inspectors recognized by the town or village where the work is done. Check any contractor in the county’s online license search before signing, and expect the building department to ask for workers’ compensation and disability insurance certificates.

How to get a building permit in Suffolk County

Review, corrections and what causes delay

SCDHS staff aim to review submissions within one to two weeks; applications with major deficiencies are returned and must start again after a meeting with staff, while minor ones are accepted and corrected in review. Local building review then depends on the town or village; the finished town guides give each office’s own timing. Filing with the town for a village parcel, or the reverse, is the most avoidable delay.

Inspections and certificates

Construction inspections and the certificate of occupancy come from the town or village building department that issued the permit. The sanitary system has its own county inspection: once it is built, the owner or installer requests an SCDHS inspection before use, then files as-built plans, and the installer certifies the system on form WWM-078. The local certificate of occupancy follows the building department’s final inspection; the town guides list the documents each office wants at that stage.

New York building code

New York builds on one statewide code, the Uniform Code, outside New York City; the 2025 edition and 2025 Energy Code took effect on 31 December 2025 (the all-electric provisions remain suspended by court order). Cities, towns and villages administer it, and local standards stricter than the code need Code Council approval. The Uniform Code in New York

In Suffolk the Uniform Code is enforced by the ten towns and 32 villages under their own local laws, alongside the county’s Sanitary Code for septic and water.

Suffolk County permit FAQ

Does Suffolk County issue building permits?

No. The towns and villages do. The county approves septic and water systems, licenses contractors and trades, and permits work on county roads.

My address says Southampton. Which office do I use?

Check whether the parcel is inside the Village of Southampton or another village such as Quogue or Sagaponack; if it is, use that village’s building department, and if not, the Town of Southampton’s.

Do I need an I/A septic system for a new house?

In most cases yes. For applications filed with SCDHS on or after July 1, 2021, Article 6 requires an innovative and alternative system for a new or expanded house or major reconstruction that uses an on-site system, with exceptions for parcels in proposed sewer districts and for projects that meet the exemption criteria, such as not being a major reconstruction and not adding bedrooms.

Does my contractor need a Suffolk County license?

A home improvement contractor needs the county license and must show its number in advertising. Some towns, such as East Hampton and Shelter Island, also issue their own home improvement licenses.

Do I need a county permit for a driveway on a county road?

Yes. Work in the county right-of-way needs a DPW highway work permit, and the town must first send the county a 239-f referral.

How long does the county take to review a septic application?

SCDHS says staff review submissions within one to two weeks, after which an accepted application is assigned a reference number and invoiced.

How do I find old permits or sanitary records?

Building permits are kept by the town or village that issued them. SCDHS records can be requested on its FOIL form, and other county records through the county FOIL portal.

Suffolk County permit search and official resources

Search town and village records through each municipality’s clerk or online permit portal; Shelter Island, for example, puts recent history online and asks for a FOIL request for older files. County sanitary, licensing and highway permit records are requested from the department concerned or through the county FOIL portal.

• SCDHS Office of Wastewater Management
• SCDHS residential sanitary permits and forms
• Suffolk County Sanitary Code, Article 6
• Suffolk County Consumer Affairs licensing
• Search licensed contractors
• County Code Chapter 563, Licensed Occupations
• DPW highway work permits
• Suffolk County towns and villages
• Town of Shelter Island Building Department
• Suffolk County FOIL request portal
• FEMA Community Status Book, New York
• NYS code adoption and enforcement updates

Simplify Suffolk County permitting with Alliance Permitting

Alliance Permitting is a permit documentation and submission company in New York. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.

This guide is provided by Alliance Permitting for general information about Suffolk County permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.