Flight number record
DL 2108
Delta Air Lines · Seattle to Chicago
- Route
- SEA → ORD
- Departs
- 17:55
- Flights
- 363
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s DL 2108, check with Delta Air Lines.
DL 2108 sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.3%. The late ones land an hour and a half behind schedule. That rests on 363 flights, with a median arrival 4 minutes early.
The national on-time rate over the same period is 77.3%, so DL 2108 runs 4 points behind the country as a whole. Across a thousand flights that is about 43 extra late arrivals.
Key figures
On time
73.0%
Arrivals under 15 minutes late, of 352 completed flights
Avg delay
91 min
Across delayed arrivals only, not all flights
Cancelled
1.38%
National rate is 1.89%
1 hour+ late
13.1%
National rate is 8.3%
These figures cover 363 flights between September 2025 and August 2026. Beyond the headline rate, 13.1% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Schedule
When DL 2108 flies
DL 2108 flies SEA to ORD without a single fixed slot. Its most common scheduled departure was 17:55, used on 200 of 363 flights, with 17:40 (57 flights) next.
- Departs 17:55200 flights55.1%
- Departs 17:4057 flights15.7%
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 17:55 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.0%, and DL 2108 runs 5 points better at 73.0%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
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Against the route
DL 2108 next to SEA to ORD
Every carrier on SEA to ORD combined arrived on time 76.7% of the time across 5,538 flights, so DL 2108 is 4 points behind it. Delta flew 922 flights on the same city pair under all its flight numbers, including this one, and those ran 75.7% on time. Across its whole network Delta Air Lines managed 81.1%, which this flight trails by 8 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 2108thin sample | 363 | 73.0% | 91 min | 1.38% | C |
| All Delta Air Lines on SEA–ORD | 922 | 75.7% | 73 min | 1.30% | B |
| All carriers on SEA–ORD | 5,538 | 76.7% | 79 min | 1.17% | B |
| Delta Air Lines, whole network | 1,039,517 | 81.1% | 71 min | 1.74% | B |
Across the year
DL 2108 quarter by quarter
DL 2108 did not run the same all year. Its best quarter was Jul–Sep 2025 at 90.0% on time and its weakest Oct–Dec 2025 at 62.5%, a swing of 28 points on roughly 73 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 202530 flights90.0%
- Oct–Dec 202591 flights62.5%
- Jan–Mar 202689 flights75.6%
- Apr–Jun 202691 flights82.0%
- Jul–Sep 202662 flights62.7%
Scale runs 55% to 95%.
By weekday, DL 2108 did best on Wednesday at 84.6% on time and worst on Monday at 66.7%. Each day rests on about 52 flights, so a gap of 18 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late DL 2108 runs when it is late
DL 2108 often beats the schedule: 98 of 352 completed flights, 28%, arrived 15 minutes or more early. The 95 late arrivals split 22 under half an hour, 27 between 30 and 60 minutes, and 46 an hour or more.
- 15+ min early98 flights27.8%
- Within 15 min159 flights45.2%
- 15–29 min late22 flights6.3%
- 30–59 min late27 flights7.7%
- 1–2 hours late21 flights6.0%
- 2+ hours late25 flights7.1%
Scale runs 0% to 100%.
Share of 352 completed flights by arrival against schedule.
19 of 97 late departures made up the time and arrived on time, 20% of them. 17 flights left on time and still arrived late.
The worst days
Worst days for DL 2108
The latest arrival of the period was on 9 January 2026, 16 hours 18 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 9 January 2026 | 16 hours 18 minutes | Carrier |
| 10 June 2026 | 5 hours 9 minutes | National Airspace System |
| 18 September 2025 | 4 hours 20 minutes | Carrier |
| 11 December 2025 | 4 hours 6 minutes | Carrier |
| 4 May 2026 | 3 hours 55 minutes | National Airspace System |
Delay causes
Why DL 2108 runs late
Carrier accounts for 43% of the 8,615 delay minutes carriers reported here, and the remaining four split what is left.
- 43%Carrier
- 29%National Airspace System
- 28%Late-arriving aircraft
The largest share of delay minutes, 43%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 3,728 of the 8,615 delay minutes reported here. The split is drawn from 8,615 delay minutes reported on DL 2108.
Cancellations sit at 1.38% against a national 1.89%, which is ordinary. Diversions add another 1.65%.
Connections and routes
What a delay on this flight costs
13.1% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
At 1,721 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
Every one of the 363 flights under DL 2108 in the data flew SEA to ORD. 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. 363 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 DL 2108
For a booking, DL 2108 is a flight to put a long connection behind. 13.1% of its completed flights arrived an hour or more late, which a short layover will not absorb. If the onward flight is on a separate ticket, the risk sits with you.
Related
Where to go next
- SEA to ORD, every carrier and departure
- ORD to SEA, the return direction
- United Airlines 747 on the same route87.5%
- Alaska Airlines 410 on the same route71.4%
- Alaska Airlines 538 on the same route82.5%
- Delta Air Lines 2055 on the same route83.4%
- Alaska Airlines 265 on the same route76.6%
- United Airlines 2618 on the same route91.4%
- Seattle-Tacoma International (SEA) delay statistics
- Chicago O'Hare International (ORD) delay statistics
- Delta Air Lines on-time record
- Every Delta Air Lines flight number with a record
- The most and least reliable flight numbers in the US
- How often a connection fails at the major US hubs
A flight number here means Delta Air Lines’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.