Be at DEN two hours before a domestic departure and three before an international one.
A maps app covers the drive to DEN. Bag drop, security, and the walk to your gate usually take longer, and they are the steps people misjudge.
Here is the same plan drawn to scale. The first block is travel; the next two are the airport. A checked bag grows one, a far gate grows the other.
Front door to boarding: 2hr 56min
Be at DEN two hours before a domestic departure and three before an international one. At an airport this size, treat those as a floor. They assume a normal day, not a holiday crush or a long security line.
DEN sits about 25 miles from downtown on the plains. The drive is long on a good day, and there is no quick version of it. Concourse A is the only one you can reach on foot, over the bridge above the taxiway; B and C are train-only, so most gates here come with a ride attached.
Denver's checkpoint lines are famously variable, and most gates require the train from the terminal out to concourse B or C, which adds a leg after security that first-time flyers don't budget. Screening is not around the clock either: both checkpoints close overnight and reopen around 3 AM, which puts a hard floor under the earliest departures.
The plan allows 30 minutes for a standard lane on a busy but normal morning. With TSA PreCheck, that drops to 15 minutes. A checked bag lengthens the one before it.
United is mostly on Concourse B and Southwest on C. Concourse A carries Delta, Frontier, JetBlue, and every foreign airline, but United's own international flights still leave from B.
The A-Line commuter train runs from Union Station to the terminal in about 37 minutes on a schedule, which makes it the most predictable way in. Driving means I-70 or E-470 plus a shuttle from the economy lots. The train comes about every fifteen minutes, so a missed one really does cost you about fifteen minutes.
For live waits, parking, and terminal maps, check the official DEN site.
Terminals, checkpoints and transit change; the official DEN site is the live source.
Be at DEN two hours before a domestic departure and three before an international one. At an airport this size, treat those as a floor. They assume a normal day, not a holiday crush or a long security line. The plan above works back from there through security, bag drop, parking and the drive to a leave-by time.
The plan allows 30 minutes for a busy-but-normal standard lane. With TSA PreCheck it drops to 15 minutes, and you can edit either one to what you actually see. A checked bag lengthens the step before it. Checkpoint detail for DEN is under Security at DEN above.
Earlier than for a domestic one. International boarding starts 45 minutes before departure instead of 30, which pulls every step earlier. Use the airline desk for bags: documents get checked and counters often close an hour out. That also covers lap infants, unaccompanied minors, and oversized bags. If your boarding pass names a boarding time, match that.
Work backward from departure: boarding, time at the gate, the walk, the ride out to your concourse, security, bag drop, parking, then the drive (40 minutes in the default plan). Replace the drive with your own route. The leave-by moment is the first travel row, "Drive to DEN" by default.
Taking the train instead? The Amtrak station pages use the same kind of plan without security. Flying from somewhere not listed? The airport leave time calculator has the same rows with your own numbers, and the wake-up time calculator runs it back to the alarm.
Start the plan in the app, and the Lock Screen and Dynamic Island show the time left, with a bar that fills as each step passes.
Glance at it in the terminal without opening the app.
Every step also gets its own alert, and sharing the plan gives whoever is driving the same leave time, with alerts on their phone.
Live Activities are part of Premium, a one-time unlock.
Plans for the rest of the trip
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