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Flight Reliability

F9 4988 · Frontier Airlines

Seattle → Salt Lake City (SEA–SLC)

67
Usually Fine
WanderNerd Reliability Score
70%
Arrive within 15 minutes
11 min
Average arrival delay
2.8%
Cancelled
1 min
Median arrival delay

Based on 107 historical flights. Data through May 2026.

What the data says

Morning-you made the right choice.

F9 4988 departing between 9 AM–12 PM arrived on time 93% of the time, versus 65% between 3–6 PM.

Skip Monday if you can.

F9 4988 arrived on time 77% of the time on Fridays. On Mondays: 68%.

Lagging the SEA–SLC route.

F9 4988 arrived on time 70% of the time, versus 84% across the SEA–SLC route.

The breakdown

On-time by weekday
  • Mon68%(40 flights)
  • Tue—(3 flights)
  • Wed—(0 flights)
  • Thu—(2 flights)
  • Fri77%(39 flights)
  • Sat—(5 flights)
  • Sun73%(15 flights)
On-time by departure window
  • 9 AM–12 PM93%(14 flights)
  • 12–3 PM65%(26 flights)
  • 3–6 PM65%(52 flights)
  • 6–9 PM75%(12 flights)
On-time trend by month
77%
Dec

Aug 77% → Dec 77% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
August 202577%13
September 202569%13
October 202583%12
November 202546%13
December 202577%13
Departures on time
72%
Diverted
0%
Flights flown
104
Months covered
11

Same route, other flights

Keep nerding

Based on 107 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.