Quote from BuildingLI.com on 10/06/2025,

Nassau County, NY – Building Departments
Municipality Type	Town/Village	Address	Phone Number	Website
Town	Hempstead	One Washington Street, 2nd Floor, Hempstead, NY 11550	(516) 538-8500	hempsteadny.gov/191/Building-Department
Town	North Hempstead	176 Plandome Road, Manhasset, NY 11030	(516) 869-6311	northhempsteadny.gov/buildings
Town	Oyster Bay	74 Audrey Avenue, Oyster Bay, NY 11771	(516) 624-6200	oysterbaytown.com/departments/planning-and-development/building/
Village	Cedarhurst	200 Cedarhurst Ave, Cedarhurst, NY 11516 (Village Hall Address)	(516) 295-5770	cedarhurst.gov/departments/building-department/
Village	Garden City	351 Stewart Avenue, Garden City, NY 11530	(516) 465-4040	gardencityny.net/168/Building-Department
Village	Hempstead	202 Jackson Street, Hempstead, NY 11550	(516) 478-6234	villageofhempstead.org/426/Building
Village	Mineola	155 Washington Avenue, Mineola, NY 11501	(516) 746-0750	mineola-ny.gov/departments
Suffolk County, NY – Building Departments
Municipality Type	Town/Village	Address	Phone Number	Website
Town	Brookhaven	1 Independence Hill, Farmingville, NY 11738	(631) 451-8696	brookhavenny.gov/284/Building-Division
Town	Huntington	Town Hall (Room 115), 100 Main Street, Huntington, NY 11743	(631) 351-2821	huntingtonny.gov/building-housing
Town	Smithtown	23 Redwood Lane, Smithtown, NY 11787	(631) 360-7520	smithtownny.gov/109/Building-Department
Town	Southampton	116 Hampton Road, Southampton, NY 11968	(631) 287-5700	southamptontownny.gov/308/Land-Management—Building-Zoning
Town	Southold	P.O. Box 1179, Southold, NY 11971	(631) 765-1802	southoldtownny.gov/98/Building-Department
Village	Babylon	153 West Main Street, Babylon, NY 11702 (Village Hall Address)	(631) 669-1300	villageofbabylonny.gov/building-department
Village	Patchogue	14 Baker Street, Patchogue, NY 11772	(631) 475-4300	patchoguevillage.gov/158/Building-Department
Village	Southampton	23 Main Street, Southampton, NY 11968	(631) 283-0247	southamptonvillage.org/150/Building-Department
Village	The Branch	40 Route 111, Smithtown, NY 11787	(631) 265-3315	smithtownny.gov/264/Village-Building-Departments