The Town FilesMountainside, New Jersey
Borough in Union County · population 7,020 (2020 Census)
- Median home
- $810,300
- Household income
- $211,538
- Jan low / Jul high
- 25° / 86°
- Snow a year
- 26 in
- Tornadoes ≤10 mi since 1950
- 17
- Median age
- 48.0
Mountainside is a borough of 7,020 people in Union County, New Jersey. The median home is worth $810,300, above the typical New Jersey town ($435,600). It ranks better for retirees than 98% of New Jersey towns, better for families than 98% of New Jersey towns, better transit than 90% of New Jersey towns.
How Mountainside ranks
Percentile among New Jersey towns with at least 500 people on The Town Files lifestyle rankings. 50 is typical for the state; 90 means better than 90% of New Jersey towns.
Homes and cost of living
The median home in Mountainside is worth $810,300, above the typical New Jersey town ($435,600). Homes cost about 3.8 times the median household income of $211,538, which is more affordable than 50% of New Jersey towns. Median rent is $3,501 a month. 87.9% of households own their home.
| Housing | Mountainside | Typical New Jersey town |
|---|---|---|
| Median home value | $810,300 | $435,600 |
| Median rent | $3,501 | $1,774 |
| Median household income | $211,538 | $111,891 |
| Home value ÷ income | 3.8× | 3.8× |
| Homeownership | 87.9% | 80.8% |
| Median year built | 1957 | 1969 |
| Seasonal / vacation homes | 0.8% | — |
Who lives in Mountainside
| People | Mountainside | Typical New Jersey town |
|---|---|---|
| Median age | 48.0 | 42.7 |
| Age 65 and over | 24.2% | 18.3% |
| Under 18 | 21.8% | — |
| Bachelor's degree or higher | 67.3% | 44.1% |
| Below the poverty line | 3.7% | 5.7% |
| Veterans | 4.4% | — |
| Born outside the U.S. | 18.9% | — |
| Work from home | 25.1% | 16.3% |
| Average commute | 36.0 min | 30.4 min |
| Homes with broadband | 99.3% | 94.6% |
Weather in Mountainside
July highs average 85.9°F and January lows 25.1°F. About 50.4 inches of rain and melted snow fall a year, with 26.3 inches of snow (typical New Jersey town: 24.5 in). Expect about 28 days a year at 90°F or hotter and 111 nights at or below freezing.
Tornadoes, storms and disasters
17 tornadoes have passed within 10 miles of Mountainside since 1950, compared with 9 for the typical New Jersey town. The strongest, an EF1, struck on October 31, 2019 about 6.0 miles from the town center. The most recent was on October 31, 2019.
Hail of 1 inch or larger has been reported within 10 miles 33 times; the largest was 1.75 inches on July 27, 2008.
Severe weather in Union County since 1996
Union County has been included in 30 federal disaster or emergency declarations since 1953, most often for fire, flood, other.
| Declared | Incident | Declaration |
|---|---|---|
| September 5, 2021 | Hurricane | DR-4614: Remnants Of Hurricane Ida |
| September 2, 2021 | Hurricane | EM-3573: Remnants Of Hurricane Ida |
| March 25, 2020 | Biological | DR-4488: Covid-19 Pandemic |
| March 13, 2020 | Biological | EM-3451: Covid-19 |
| March 14, 2016 | Severe Storm | DR-4264: Severe Winter Storm And Snowstorm |
Jobs and pay in Union County
Union County had 229,010 jobs in 2024, paying an average of $84,322 a year. Unemployment was 4.7% in 2023; in Mountainside itself the ACS puts it at 3.5%.
Public schools in Mountainside
2 public schools with 748 students, about 10.4 students per teacher.
| School | Grades | Students | Per teacher |
|---|---|---|---|
| Deerfield Elementary School | 3-8 | 488 | 10.2 |
| Beechwood School | PK-2 | 260 | 10.8 |
Towns near Mountainside
- Springfield, NJ1.8 mi · 17,178 people · home $636,600
- Westfield, NJ2.2 mi · 31,032 people · home $953,400
- Summit, NJ2.4 mi · 22,719 people · home $994,500
- New Providence, NJ2.7 mi · 13,650 people · home $769,900
- Garwood, NJ2.8 mi · 4,454 people · home $533,300
- Fanwood, NJ3.0 mi · 7,774 people · home $635,200
- Berkeley Heights, NJ3.3 mi · 13,285 people · home $789,400
- Scotch Plains, NJ3.4 mi · 24,968 people · home $718,200
Mountainside questions
Is Mountainside, New Jersey a good place to retire?
On The Town Files lifestyle rankings, Mountainside scores better for retirees than 98% of New Jersey towns and quieter than 67%. 24.2% of residents are 65 or older (median age 48.0).
How much does a house cost in Mountainside?
The median owner-occupied home in Mountainside is valued at $810,300 (Census ACS 2020–2024), against a median household income of $211,538, so homes cost about 3.8 times income. Median rent is $3,501 a month.
What is the weather like in Mountainside?
July highs average 85.9°F and January lows 25.1°F (NOAA 1991–2020 normals). It gets about 50.4 inches of precipitation a year and 26.3 inches of snow.
Does Mountainside get tornadoes?
17 tornadoes have passed within 10 miles of Mountainside since 1950 (NOAA Storm Events); the strongest was an EF1 on October 31, 2019. The typical New Jersey town has had 9.
- U.S. Census Bureau, American Community Survey 5-year estimates (2020–2024)
- U.S. Census Bureau, 2020 Census and 2025 Gazetteer (2020 / 2025)
- NOAA NCEI U.S. Climate Normals (1991–2020)
- NOAA NCEI Storm Events Database (1950–2026)
- FEMA OpenFEMA Disaster Declarations (this product uses the FEMA OpenFEMA API but is not endorsed by FEMA) (1953–2026)
- NCES Common Core of Data (2023–24)
- BLS Quarterly Census of Employment and Wages; USDA ERS county unemployment (BLS LAUS) (2000–2024)
- The Town Files lifestyle rankings, built from federal demographic, school, crime and housing data (2025)