How Container Terminal Wait Times Are Measured
Not all “wait time” numbers are created the same way. Here’s exactly how dwell time is captured at major ports and what the data actually represents.
If you move containers through ports like the Port of Houston, you’ve probably seen “average wait time” numbers on carrier sites, terminal dashboards, or third-party tools. These numbers can vary dramatically depending on how they are collected.
Understanding the measurement method is important because it determines how reliable the number is for planning your own moves.
Two common ways wait times are reported
1. Terminal Operating System (TOS) data
Many terminals publish official queue or turn time statistics based on their own systems (N4, Tideworks, etc.). These numbers reflect gate transactions recorded by the terminal.
- • Often includes only trucks that actually entered the gate
- • Can vary based on how the terminal defines “wait” vs “in-terminal time”
- • Usually aggregated and may lag by hours or a day
2. Carrier / fleet GPS + geofence data
Some operators publish wait times measured directly from their own trucks using GPS devices and virtual geofences around the terminal.
- • Captures the full experience from approach through exit
- • Reflects real-world conditions for that specific fleet
- • Can be updated daily or more frequently
- • Limited to the trucks the carrier actually operates
How GPS + geofence measurement works
Modern measurement typically works like this:
- A virtual geofence (a defined geographic boundary) is drawn around the terminal entry and exit points.
- Every truck in the fleet carries a GPS unit (for example, Samsara or similar ELD/telematics devices).
- When a truck crosses into the geofence, the system logs an “entry” timestamp.
- When the same truck crosses out of the geofence, the system logs an “exit” timestamp.
- The difference between entry and exit is recorded as dwell time (total time inside the terminal area).
- These individual truck dwells are averaged by day (and sometimes by hour of day) to produce the published statistics.
What the published numbers actually represent
Daily average
The mean dwell time across all qualifying trucks from that fleet on a given calendar day. Days with very few measurements are often excluded so one slow move doesn’t distort the picture.
Hourly windows
Many operators also break the data into 2-hour windows (e.g., 6–8 AM, 2–4 PM). This helps identify the best and worst times of day to arrive.
Trend
Comparing this week’s average to last week’s shows whether conditions are improving, stable, or getting worse.
Sample considerations
The more trucks a carrier runs through a terminal, the more statistically meaningful the average becomes. Small sample sizes should be viewed with caution.
Important limitations to understand
- •Own-fleet bias: The numbers only reflect the experience of the trucks that operator actually runs. A different carrier or a broker’s drayage partner may see different results on the same day.
- •Not universal: These are not official terminal statistics. They are operational telemetry from one fleet.
- •Appointment and container variables: Wait times can be heavily influenced by whether a truck has a good appointment, the steamship line, container type, and chassis availability.
- •Definition matters: Make sure you understand exactly what “wait time” includes before comparing numbers across different sources.
How shippers and brokers can use this data
Transparent wait time data is most useful when you treat it as one signal among several:
- • Use it to set realistic expectations with your customers about delivery windows.
- • Look at trends and time-of-day patterns rather than any single day’s number.
- • Combine it with other information (appointment availability, chassis supply, known construction or weather issues).
- • Ask carriers how they measure their numbers so you can compare apples to apples.
See current conditions at Bayport and Barbours Cut
Live daily averages and hourly patterns measured from active fleet operations.
View live port wait times