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Flight Reliability

F9 1820 · Frontier Airlines

Phoenix → Denver (PHX–DEN)

85
Pretty Reliable
WanderNerd Reliability Score
79%
Arrive within 15 minutes
7 min
Average arrival delay
0.6%
Cancelled
6 min early
Median arrival delay

Based on 171 historical flights. Data through May 2026.

What the data says

The 3–6 PM departure wins.

F9 1820 departing between 3–6 PM arrived on time 90% of the time, versus 63% between 6–9 PM.

Mondays have been rough.

F9 1820 arrived on time 89% of the time on Saturdays and just 72% on Mondays. That gap is worth planning around.

A bit ahead of the Frontier Airlines network.

F9 1820 arrived on time 79% of the time, versus 73% across the Frontier Airlines network.

Recent months have been rougher.

F9 1820 arrived on time 81% of the time over the last three months in the data, compared with 92% in the three months before that.

The breakdown

On-time by weekday
  • Mon72%(32 flights)
  • Tue—(4 flights)
  • Wed—(8 flights)
  • Thu84%(32 flights)
  • Fri75%(32 flights)
  • Sat89%(26 flights)
  • Sun86%(36 flights)
On-time by departure window
  • 3–6 PM90%(10 flights)
  • 6–9 PM63%(48 flights)
  • 9 PM–12 AM86%(112 flights)
On-time trend by month
91%
May

Sep 71% → May 91% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
September 202571%21
October 202583%18
November 202579%19
December 202590%19
January 202693%15
February 202694%16
March 202656%25
April 202695%19
May 202691%11
Departures on time
76%
Diverted
0%
Flights flown
170
Months covered
10

Same route, other flights

Keep nerding

Based on 171 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.