Need segment-level traffic data?

Identify traffic patterns street by street and analyze the exact corridors that matter to your project.

Get insights →
Traffic heat map of Mercer County, New Jersey: 622 miles of roads shaded from blue (light) to red (heavy traffic), busiest on Brunswick Pike and NJ 29

Mercer County, New Jersey Traffic Counts

Its highways carry one of the top 5 truck shares of any county in New Jersey. This page breaks down traffic in Mercer County, New Jersey across 622 miles of monitored roads split into 18,036 segments, using multi-sourced mobile and sensor data. It goes beyond raw counts to truck flow, congestion and who is driving, so site selection and route planning rest on evidence.
Data sourced from TrafficZoom's proprietary analytics platform.
Data current as of:
Q3 2026
Updated:
September 29, 2026
Find my place
total traffic icon

Total Traffic Volume & Performance in Mercer County, New Jersey

Traffic

The average number of vehicles that travel each day over any road in the road network.

vehicles per day7,849
Trucks

The percentage of the total traffic volume composed of heavy vehicles.

9.6%
Average travel time

The average time of travel averaged among all vehicles traveling on the road network.

35.4 min
Congestion ratio

The rate at which the actual travel time exceeds free-flow travel time, averaged among all roads in the network.

23.1%
Drivers’ average age

Average age of residents in the geographic areas where the vehicle trips originated.

47.5 yrs
Drivers’ average income

Average income of residents in the geographic areas where the vehicle trips originated.

$129,224

Our data shows 7,849 vehicles per day on the average road in Mercer County, New Jersey, and 5,871,435 vehicle-miles traveled per day (≈2.1 billion per year) across its 622 miles of monitored roads. At 9.6%, the truck share runs above the 7.9% across New Jersey: about 1 in 10 vehicles.

Longer trips than 90% of counties in New Jersey

At 7,849 vehicles per day, the average road in Mercer carries somewhat less traffic than the state average of 8,886 (12% less) - a critical factor for logistics and site planning. Across the whole network, that travel is about 3.8% of New Jersey's statewide total. By volume, Mercer's 7,849 vehicles per day trails 55% of counties in New Jersey.

Journey times run 6% higher than the state level, at 35.4 minutes on average. Its average travel time of 35.4 minutes is longer than 90% of counties in New Jersey.

Congestion is somewhat lower than the state level, at a ratio of 23.1% (15% lower) - crucial for traffic control improvement and logistics planning.

Highway vs. Non-Highway Traffic Analysis

highway traffic icon

Highway Traffic in Mercer County, New Jersey

Trafficvehicles per day16,962
Trucks14.2%
Average travel time40.5 min
Congestion ratio31.0%
Drivers’ average age47.6 yrs
Drivers’ average income$133,483

Travel in Mercer County, New Jersey splits roughly evenly, with about half of it (53% of vehicle-miles) on highways. The average highway carries 16,962 vehicles per day, 136% more than the average non-highway road in the same area, which carries 7,181 vehicles per day.

Highways make up 27% of the monitored road miles (171 miles, 1,232 segments), so they carry more than their share: 3,138,710 vehicle-miles traveled per day (≈1.1 billion per year).

Higher highway truck share than 85% of counties in New Jersey

The concentration of trucks on highways (14.2%) is 39% higher than the state average for similar road classifications. Highways here lean toward freight, so highway access is a real asset for logistics operators.

Mercer's highway truck share (14.2%) is higher than 85% of counties in New Jersey. 60% of counties in New Jersey see fewer highway trucks per day than Mercer's roughly 2,415.

non-highway traffic icon

Non-highway Traffic in Mercer County, New Jersey

Trafficvehicles per day7,181
Trucks4.2%
Average travel time35.0 min
Congestion ratio22.5%
Drivers’ average age47.3 yrs
Drivers’ average income$126,901

Travel in Mercer County, New Jersey splits roughly evenly, with about half of it (47% of vehicle-miles) on local roads. The average non-highway road carries 7,181 vehicles per day.

Spread over 452 miles and 16,804 segments, 73% of the road network, local roads carry a lighter load per mile: 2,732,725 vehicle-miles traveled per day (≈997 million per year). About 1 in 24 vehicles on non-highway roads is a truck (4.2%).

Local roads carry 71% fewer trucks by share than highways

Non-highway roads carry a truck concentration that's 71% lower than the highway network.

Non-highway congestion (22.5%) runs slightly lower than the state level (8% lower).

Trip origins here have higher average income than 65% of counties in New Jersey. Mercer's median driver age is lower than 60% of counties in New Jersey.

Time-of-Day & Seasonal Patterns

peak hours icon
Peak Traffic Windows
Weekday peaks:
AM peak 7:00 AM–9:00 AM and a long afternoon plateau from 12:00 PM to 7:00 PM, with volumes reaching approximately 63% higher than the daily average.
Weekend traffic:
Weekends are much quieter: volumes run about 24% below weekday levels, the signature of a commute-driven road network.
seasonal traffic icon
Seasonal Fluctuation
Busy season:
August–October is the high season, with volumes +5% versus the annual average.
Lowest month:
January is the quietest month, with volumes -8% versus the annual average - the usual winter low.

Data Finding: Hourly & Seasonal Patterns

In Mercer County, New Jersey, the peak hour concentrates about 7% of the day's traffic, and there is a noticeable seasonal swing of +5% in high season.

Mercer County vs. New Jersey Traffic Comparison

The highway truck share sets Mercer County apart: 39% above the New Jersey average. Its truck share is also 20% above.

MetricMercer CountyNew Jersey averageDifference
Traffic7,8498,886-11.7%
Truck % (Total Traffic)9.6%7.9%+20.4%
Truck % (Highway)14.2%10.2%+39.5%
Avg. Travel Time35.4 min33.4 min+6.0%

How Mercer County compares

Mercer County against nearby counties

Mercer County tracks the 4 areas around it closely - no measure in this table sets it far apart from the areas immediately next to it, though it has the third busiest roads of the five. The same kind of road, just less of it: traffic per road matches the areas around it while the network itself is smaller.

Mercer County and the 4 nearest county-level areas by centroid distance, with the New Jersey average for scale.
AreaAverage daily trafficTruck shareDaily vehicle-milesAverage travel timeCongestion ratio
Mercer County7,8499.6%5,871,43535.4 min23.1%
Somerset County, New Jersey7,8547.8%7,289,29333.0 min23.1%
Middlesex County, New Jersey11,9778.9%16,312,25333.0 min33.5%
Bucks County, Pennsylvania7,3036.4%10,013,19932.9 min20.1%
Hunterdon County, New Jersey5,23011.0%3,591,63435.4 min14.0%
New Jersey average8,8867.9%N/A33.4 min27.0%

Mercer County ranked within New Jersey

Mercer County sits in New Jersey's top three on average travel time.

Mercer County ranked among 21 county-level areas in New Jersey (1 = highest).
MeasureMercer CountyNew Jersey rank
Traffic volume (AADT)7,849#12 of 21
Highway vehicle-miles per day3,138,710#13 of 21
Truck share on highways14.2%#4 of 21
Highway trucks per day2,415#9 of 21
Average travel time35.4 min#3 of 21
Average driver income$129,224#8 of 21
Average driver age47.5 yrs#13 of 21

Busiest roads in Mercer County, New Jersey

The three busiest roads in Mercer County average 55,953 vehicles a day, 7.1 times the county average of 7,849 across all its monitored roads.

Brunswick Pike leads with 58,985 vehicles a day, 4,989 of them trucks (8.5%). New Jersey Turnpike carries the most trucks, 11,319 a day (32.8% of its traffic), although it is not among the 5 busiest roads overall.

Trucks make up 32.8% of traffic on New Jersey Turnpike, against 9.6% across all roads in the county.

Trips using New Jersey Turnpike are long: a median of 67.3 minutes against 35.4 county-wide, the mark of a through route.

Ranked by daily traffic (AADT)

Cars and light vehiclesTrucks
1Brunswick PikeTrunk road · 58,985vehicles4,989trucks · 8.5%
Road class
Trunk road
Congestion ratio
50.1%
Median trip time
39.6 min
Drivers’ median age
46.7 yrs
Drivers’ average income
$143,713

Delays build on Brunswick Pike: its congestion ratio of 50% over free-flow time is well above the county's 23%.

2NJ 29Motorway · 56,126vehicles4,711trucks · 8.4%
Road class
Motorway
Congestion ratio
41.4%
Median trip time
40.7 min
Drivers’ median age
48.0 yrs
Drivers’ average income
$113,372

NJ 29 is a trunk route for the county, carrying 7.2 times the county average on its busiest stretch; trucks are 8.4% of it, below the county-wide 9.6%.

3Central Jersey ExpresswayMotorway · 52,749vehicles5,548trucks · 10.5%
Road class
Motorway
Congestion ratio
47.3%
Median trip time
44.1 min
Drivers’ median age
48.1 yrs
Drivers’ average income
$129,270

Travel on Central Jersey Expressway's busiest stretch runs 47% over free-flow time, against 23% across the county, so expect slower peak hours.

4US 1Trunk road · 48,763vehicles4,066trucks · 8.3%
Road class
Trunk road
Median trip time
41.1 min
Drivers’ median age
46.7 yrs
Drivers’ average income
$151,597

US 1 carries 6.2 times the county average at its busiest, 4,066 of them trucks (8.3%, below the county-wide 9.6%).

5Camden FreewayMotorway · 40,423vehicles3,381trucks · 8.4%
Road class
Motorway
Congestion ratio
29.2%
Median trip time
38.9 min
Drivers’ median age
48.1 yrs
Drivers’ average income
$135,657

Camden Freeway carries 5.1 times the county average on its busiest stretch, where the median trip lasts 38.9 minutes.

Ranked by trucks per day

Cars and light vehiclesTrucks
1New Jersey TurnpikeMotorway · 34,554vehicles11,319trucks · 32.8%
Road class
Motorway
Congestion ratio
24.9%
Median trip time
67.3 min
Drivers’ median age
47.8 yrs
Drivers’ average income
$145,701

New Jersey Turnpike carries 4.4 times the county average on its busiest stretch, where the median trip lasts 67.3 minutes.

2Central Jersey ExpresswayMotorway · #3 by traffic52,749vehicles5,548trucks · 10.5%
3Brunswick PikeTrunk road · #1 by traffic58,985vehicles4,989trucks · 8.5%
4NJ 29Motorway · #2 by traffic56,126vehicles4,711trucks · 8.4%
5US 1Trunk road · #4 by traffic48,763vehicles4,066trucks · 8.3%
How to read these road counts
  • The first number is AADT, annual average daily traffic: the vehicles passing a point on an average day, both directions combined and trucks included. On a divided highway both carriageways are added together.
  • Traffic changes along a road, with more near interchanges and towns and less in open country. Every figure for a road describes its busiest stretch in the county, so the two rankings show the same numbers for the same road.
  • The second number is the trucks on that stretch, a part of its AADT. The bar splits the AADT into cars and light vehicles (blue) and trucks (amber).
  • See segment-level AADT for any road on TrafficZoom.

Data Sources & Methodology

The data presented on this page is derived from TrafficZoom's proprietary analytics platform, which aggregates and normalizes information from multiple sources, including:

Mobile device location data (anonymized and aggregated)

Road sensor networks and traffic counters

Historical traffic pattern databases

Public traffic count programs published by the

MercerDepartment of Transportation

Demographic Baseline for O-D Modeling

U.S. Census Bureau
All metrics represent estimates based on statistical modeling and are intended for strategic planning purposes.
link arrow icon
Data current as of:
Q3 2026

Explore further

TrafficZoom platform

— street-level analytics and custom corridor reports.

Map AI

— demographics, housing and mobility data.

Counties near Mercer County

The same traffic breakdown for the areas closest to Mercer County, New Jersey.

Need segment-level traffic data?

Identify traffic patterns street by street and analyze the exact corridors that matter to your project.