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Flight Reliability

F9 4855 · Frontier Airlines

Houston → Denver (IAH–DEN)

93
Nerd Approved
WanderNerd Reliability Score
85%
Arrive within 15 minutes
8 min early
Average arrival delay
0%
Cancelled
21 min early
Median arrival delay

Based on 67 historical flights. Data through May 2026.

What the data says

The 3–6 PM departure wins.

F9 4855 departing between 3–6 PM arrived on time 100% of the time, versus 78% between 9 PM–12 AM.

Friday comes out ahead.

A small edge: 75% on time on Fridays against 70% on Saturdays.

A bit ahead of the IAH–DEN route.

F9 4855 arrived on time 85% of the time, versus 82% across the IAH–DEN route.

Better than the Frontier Airlines network average.

F9 4855 arrived on time 85% of the time, versus 73% across the Frontier Airlines network.

The breakdown

On-time by weekday
  • Mon—(9 flights)
  • Tue—(9 flights)
  • Wed—(9 flights)
  • Thu—(9 flights)
  • Fri75%(12 flights)
  • Sat70%(10 flights)
  • Sun—(9 flights)
On-time by departure window
  • 9 AM–12 PM92%(12 flights)
  • 12–3 PM—(3 flights)
  • 3–6 PM100%(11 flights)
  • 9 PM–12 AM78%(41 flights)
On-time trend by month
82%
May

Mar 85% → May 82% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
March 202685%26
April 202685%26
May 202682%11
Departures on time
82%
Diverted
0%
Flights flown
67
Months covered
4

Same route, other flights

Keep nerding

Based on 67 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.