Anthony Licciardello | June 20, 2026
Mountainside, NJ
Property Taxes · Mountainside, NJ
In a state famous for crushing property taxes, Mountainside holds a genuinely unusual position: its effective tax rate is among the lowest in all of Union County. That's a real ownership-cost advantage — but only if you understand what it does and doesn't mean. The dollar figure on a Mountainside tax bill isn't small, because the homes are valuable. The advantage lives in the rate you pay per dollar of that value, which is where Mountainside quietly beats almost every town around it. Here's how to read it honestly.
This guide is part of our complete coverage of the borough. For the full picture, start at our complete guide to buying and selling in Mountainside.
Most people compare towns by the average tax bill, and that's exactly the wrong tool. A town that taxes a $1 million home $16,000 and a town that taxes a $550,000 home $11,000 are charging a similar proportional rate — the first owner just holds a more valuable asset. The honest metric for comparing towns is the effective tax rate: the annual tax divided by the home's true market value. On that measure, Mountainside's effective rate of roughly 1.57% sits among the lowest in Union County — behind only Summit and below names like Westfield. So yes, a Mountainside bill runs into five figures, but the rate behind it is unusually gentle for the area.
For the full cross-town picture, see our Union County property-tax comparison, which ranks the central-county towns by effective rate.
From the Broker
“Buyers see a Mountainside tax bill and flinch — until I show them the effective rate. Per dollar of home value, it's one of the lowest in the county. You're not paying a premium to live here on taxes; if anything, the rate is part of the value.”
Anthony Licciardello, Broker, The Prodigy Team
Two forces work in residents' favor. First, the borough's Route 22 commercial corridor: businesses along that strip pay into the tax base, sharing a load that falls more heavily on homeowners in purely residential towns. Second, high home values themselves spread the municipal and school levy across a large pool of assessed value, which compresses the rate each dollar of value carries. Together, the commercial ratables and the strong values keep Mountainside's effective rate near the bottom of the county — an advantage most affluent New Jersey towns simply don't have.
A favorable rate doesn't excuse you from doing the homework on a specific home. Pull the property's current assessed value and its actual annual tax, since that's what you'll pay, not a borough average. Factor in any relief you may qualify for, such as the state's ANCHOR program or senior benefits. And ask whether a townwide revaluation or reassessment may be on the horizon, since that can reset assessed values and shift individual bills. The rate tells you the town's posture; the specific bill tells you your cost.
Watch Out
A low rate is not a low bill. On a $1 million-plus home, even a gentle effective rate produces a five-figure annual tax — budget for the real dollars, not just the favorable percentage. And always confirm the specific property's assessment and current bill rather than relying on a townwide figure.
Tax rates, assessments, and relief programs change and vary by property; figures here are approximate and drawn from certified county data as of 2025. This is general information, not tax or financial advice — confirm current figures with the Mountainside tax assessor and a qualified professional.
For buyers, the low effective rate is a quiet but durable part of Mountainside's value — an affluent, wooded town that doesn't punish you on the tax line the way many premium New Jersey towns do. For sellers, it's a selling point worth making explicit, especially to New York and Staten Island buyers comparing total ownership costs across towns. It pairs naturally with the borough's other advantages: see the case for New York buyers moving to Mountainside, and when it's time to list, our guide to selling a Mountainside home.
Want the real tax math on a specific home?
Comparing towns on the sticker bill leads buyers astray. The Prodigy Team runs the effective-rate and all-in ownership math on the actual home you're considering — and helps sellers make the tax advantage part of the pitch to out-of-area buyers. We work both sides of the water.
Anthony Licciardello, Broker, The Prodigy Team · 718-873-7345
See What Your Mountainside Home Is Worth
Mountainside's effective property-tax rate, around 1.57%, is among the lowest in Union County. Because home values are high, the actual dollar bill is not small — typically in the five figures — but the rate you pay per dollar of home value is unusually favorable for the area.
Based on 2025 certified county data, Mountainside's effective tax rate is roughly 1.57%, placing it near the bottom of Union County, behind only Summit. Rates change year to year, so confirm the current figure and your specific property's assessment before relying on it.
Two factors help: the Route 22 commercial corridor adds business ratables that share the tax burden, and high residential values spread the levy across a large pool of assessed value. Together they compress the effective rate, an advantage most affluent New Jersey towns lack.
Look up the property's current assessed value and its actual annual tax rather than a borough average, factor in any relief such as the ANCHOR program, and confirm details with the Mountainside tax assessor. For a purchase decision, have a qualified professional review the specific numbers.
Prodigy Real Estate is an innovative real estate company offering high-end video production, home valuation services, purchasing, and home sales. Serving New York and New Jersey.
