Flight number record
F9 688
Frontier Airlines · Denver to Washington
- Route
- DEN → DCA
- Departs
- 11:25
- Flights
- 312
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s F9 688, check with Frontier Airlines.
F9 688 lands a B, about a point worse than the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That rests on 312 flights, with a median arrival 8 minutes early.
Key figures
On time
76.0%
Arrivals under 15 minutes late, of 304 completed flights
Avg delay
77 min
Across delayed arrivals only, not all flights
Cancelled
1.60%
National rate is 1.89%
1 hour+ late
7.9%
National rate is 8.3%
These figures cover 312 flights between September 2025 and August 2026. The median arrival is 8 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
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Schedule
When F9 688 flies
F9 688 flies DEN to DCA without a single fixed slot. Its most common scheduled departure was 11:25, used on 79 of 312 flights, with 11:38 (67 flights) and 11:37 (65 flights) next.
- Departs 11:2579 flights25.3%
- Departs 11:3867 flights21.5%
- Departs 11:3765 flights20.8%
Scale runs 0% to 100%.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 11:25 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.3%, and F9 688 runs 2 points worse at 76.0%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
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Against the route
F9 688 next to DEN to DCA
Every carrier on DEN to DCA combined arrived on time 80.6% of the time across 1,347 flights, so F9 688 is 5 points behind it. Frontier flew 983 flights on the same city pair under all its flight numbers, including this one, and those ran 77.5% on time. Across its whole network Frontier Airlines managed 72.7%, which this flight beats by 3 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| F9 688thin sample | 312 | 76.0% | 77 min | 1.60% | B |
| All Frontier Airlines on DEN–DCA | 983 | 77.5% | 72 min | 0.81% | B+ |
| All carriers on DEN–DCA | 1,347 | 80.6% | 70 min | 0.67% | B+ |
| Frontier Airlines, whole network | 213,022 | 72.7% | 84 min | 2.05% | C |
Across the year
F9 688 quarter by quarter
F9 688 did not run the same all year. Its best quarter was Oct–Dec 2025 at 79.3% on time and its weakest Jul–Sep 2026 at 65.3%, a swing of 14 points on roughly 78 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
- Jul–Sep 202526 flights—
- Oct–Dec 202582 flights79.3%
- Jan–Mar 202676 flights78.1%
- Apr–Jun 202676 flights78.7%
- Jul–Sep 202652 flights65.3%
Scale runs 55% to 85%. Rows with fewer than 30 flights show a dash.
By weekday, F9 688 did best on Saturday at 91.7% on time and worst on Tuesday at 66.7%. Each day rests on about 45 flights, so a gap of 25 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late F9 688 runs when it is late
F9 688 often beats the schedule: 105 of 304 completed flights, 35%, arrived 15 minutes or more early. The 73 late arrivals split 30 under half an hour, 19 between 30 and 60 minutes, and 24 an hour or more.
- 15+ min early105 flights34.5%
- Within 15 min126 flights41.4%
- 15–29 min late30 flights9.9%
- 30–59 min late19 flights6.3%
- 1–2 hours late15 flights4.9%
- 2+ hours late9 flights3.0%
Scale runs 0% to 100%.
Share of 304 completed flights by arrival against schedule.
15 of 71 late departures made up the time and arrived on time, 21% of them. In the other direction, 17 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at DCA.
The worst days
Worst days for F9 688
The latest arrival of the period was on 23 February 2026, 17 hours 59 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). On four of the five worst days the largest share was filed as national airspace system delay.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 23 February 2026 | 17 hours 59 minutes | Carrier |
| 12 June 2026 | 6 hours 29 minutes | National Airspace System |
| 26 January 2026 | 5 hours 53 minutes | National Airspace System |
| 9 July 2026 | 4 hours 27 minutes | National Airspace System |
| 7 November 2025 | 3 hours 34 minutes | National Airspace System |
Delay causes
Why F9 688 runs late
National Airspace System accounts for 48% of the 5,623 delay minutes carriers reported here, and the remaining four split what is left.
- 48%National Airspace System
- 34%Carrier
- 18%Late-arriving aircraft
- 0%Extreme weather
48% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 2,694 minutes out of 5,623, against a national NAS share of 21%. The split is drawn from 5,623 delay minutes reported on F9 688.
Cancellations sit at 1.60% against a national 1.89%, which is ordinary. Diversions add another 0.96%.
Connections and routes
What a delay on this flight costs
7.9% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
The 1,476 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.
Every one of the 312 flights under F9 688 in the data flew DEN to DCA. The number was not reused on any other city pair, which makes this a clean record of one route.
One caution: this is a thin sample. 312 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking F9 688
For a booking, read F9 688 as 76.0% on time with 1.60% cancelled over 312 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- DEN to DCA, every carrier and departure
- DCA to DEN, the return direction
- Frontier Airlines 690 on the same route65.7%
- Frontier Airlines 686 on the same route92.6%
- United Airlines 789 on the same route90.9%
- Denver International (DEN) delay statistics
- Ronald Reagan Washington National (DCA) delay statistics
- Frontier Airlines on-time record
- Every Frontier Airlines flight number with a record
- The most and least reliable flight numbers in the US
- The best day of the week to fly, and why it is the second lever
A flight number here means Frontier Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.