Town guide · Middlesex County
Living in South Plainfield, NJ
South Plainfield is a borough of about eight square miles on the Union County line, with Interstate 287 crossing its southern end. It is home to the 127 acre Spring Lake Park and to the site of Hadley Field, where the country's first overnight airmail flight took off in 1925.
- County
- Middlesex
- Population
- About 24,300 (2020 census)
- Size
- About 8.3 square miles
- Setting
- Suburban borough with neighborhoods, parkland and commercial and industrial areas
- Main roads
- Interstate 287 (Exits 4 and 5), Park Avenue (County Route 531), Stelton Road (County Route 529) and New Durham Road (County Route 501)
First things first
Not part of Plainfield
South Plainfield is its own borough in Middlesex County. It is not part of the City of Plainfield, which sits just to the north in Union County, and it has its own government and its own property tax rate. It was carved out of Piscataway Township in 1926.
The borough uses the 07080 ZIP code. When we price a home near the Plainfield, Piscataway or Edison lines, we confirm the actual municipality and block and lot first.
Neighborhoods
Named places in a compact borough
South Plainfield was incorporated in 1926 from part of Piscataway Township and takes its name from neighboring Plainfield. It borders Piscataway to the south and west, Edison to the east, and Plainfield and Scotch Plains to the north.
- Samptown: One of the borough's oldest place names. The hamlet of Sampton grew up where Sampton and Clinton Avenues meet, on the old road from Elizabeth to New Brunswick, and a tavern for travelers stood at what is now 746 Sampton Avenue in the late 1700s.
- Brooklyn: An early hamlet at Front Street and South Plainfield Avenue. A sawmill and gristmill started along Cedar Brook in 1732.
- Holly Park: Named for a 1940s amusement park with a swimming lake, on the site of today's PAL building.
- Avon Park: Another named area within the borough.
- Hadley Airport: The area of the old Hadley Field, an airfield from 1924 to 1928 where pilot Dean C. Smith took off on the first overnight airmail run in 1925. The site later held a Nike missile battery and is now a shopping center.
Homes
What you will find
- Postwar neighborhoods: After World War II, housing developments spread across the north side of the borough, and they make up much of South Plainfield's residential land today.
- Homes near parkland: Streets around Spring Lake Park, Cedar Brook Park on the Plainfield line, and the Dismal Swamp along the Edison line.
- Homes near commercial and industrial areas: Parts of the borough are close to industrial land and shopping, so it pays to know what is next door.
Worth knowing: South Plainfield has an industrial past. The former Cornell Dubilier Electronics plant is a federal Superfund site, and the EPA has run a long cleanup of PCBs there, along the Bound Brook and its floodplain, and on some nearby residential properties. For homes near the Bound Brook or the old plant, we look up the flood zone and the environmental record early so buyers and sellers have the facts.
Property taxes
What taxes look like in South Plainfield
- 2.023%2025 effective tax rate, as a share of market value
- $9,1552025 average residential tax bill
A home worth $450,000 on today's market would pay roughly $9,104 a year at South Plainfield's 2025 effective rate. Your actual bill depends on your assessment, so we pull the real tax record for any home you are considering.
Source: New Jersey Division of Taxation, 2025 general and effective tax rates. Rates are set each year.
Getting around
Roads and commuting
Interstate 287 crosses the southern part of the borough for about two miles, with Exits 4 and 5, and connects to the New Jersey Turnpike in Edison. Park Avenue (County Route 531) runs along the east side of town between Edison and Plainfield, Stelton Road (County Route 529) runs along the southwestern border with Piscataway, and New Durham Road (County Route 501) runs along the southern border. There is no passenger train station in South Plainfield. The closest is Netherwood in Plainfield, on NJ Transit's Raritan Valley Line.
Places worth knowing
Parks, landmarks and open space
- Spring Lake Park: A 127 acre Middlesex County park on Plainfield Avenue built around a five acre lake, with walking trails, a bike path, fishing, a gazebo, a performance stage, tennis and basketball courts and a playground.
- Cedar Brook Park: A 78 acre Union County park designed by the Olmsted Brothers, mostly in Plainfield with a smaller part in South Plainfield, known for its Shakespeare Garden and a lake on Cedar Brook. It is listed on the National Register of Historic Places.
- Dismal Swamp: Nearly 650 acres of wetland and woods in Edison, South Plainfield and Metuchen. Middlesex County preserves about 120 acres of it, and the Middlesex Greenway rail trail reaches part of it.
Common questions
Questions people ask us about South Plainfield
What are property taxes in South Plainfield, NJ?
South Plainfield Borough's 2025 effective tax rate is 2.023 percent of market value, and the average residential tax bill is $9,155, according to the New Jersey Division of Taxation. Actual bills depend on each home's assessment.
Is South Plainfield part of Plainfield?
No. South Plainfield is a separate borough in Middlesex County, formed from part of Piscataway Township in 1926. Plainfield is a separate city in Union County, just to the north.
Which Interstate 287 exits serve South Plainfield?
Exits 4 and 5. Interstate 287 runs through the southern part of the borough for about two miles and connects to the New Jersey Turnpike in nearby Edison.
Is there a train station in South Plainfield?
No. South Plainfield has no passenger train station. The closest is Netherwood in Plainfield, just to the north, on NJ Transit's Raritan Valley Line.
What was Hadley Field?
Hadley Field was an airfield in South Plainfield from 1924 to 1928 and an early stop for airmail service. The first overnight airmail run left from there on July 1, 1925. The site later held a Nike missile battery and is now a shopping center.
Nearby towns
Towns that border South Plainfield
Buying or selling in South Plainfield?
Facts first, then price
Near the Bound Brook or the old Cornell Dubilier site, the flood zone and the environmental record come first. We gather those facts on each South Plainfield home before we talk numbers, then explain your options.
Call or text either of us directly.