Informational Guide to Seattle–Tacoma Airport - Seatac (SEA) - NON OFFICIAL

DL20 Delta Air Lines - Flight Status

Below, you can find details about Delta Air Lines flight DL20, which currently operates between the airports of Seattle - Seattle-Tacoma International Airport (Airport Code SEA) and London - London Heathrow Airport (Airport Code LHR).
This flight data pertains specifically to the flight's details for Saturday, December 27, 2025.

DL20 On Time performance:
75
We have calculated the percentage of flights that arrived within 15 minutes of their scheduled time, or earlier, based on real flight data from the last 3 months. More about punctuality and delays

Flight Status

DL20 Delta Air Lines to London

Scheduled - On-time
Flight Status for Saturday December 27, 2025
This flight was also scheduled for Yesterday (December 26, 2025). See it here
This flight is also scheduled for Tomorrow (December 28, 2025). See it here

Airline information

Delta Air Lines
Delta Air Lines
Equipment: Airbus A330-200

Departure

Seattle (SEA)
December 27, 2025
Seattle-Tacoma International Airport
Estimated Departure Time:
04:48 pm
Gate:
A11
Scheduled Departure Time: 04:48 pm

Arrival

London (LHR)
December 28, 2025
London Heathrow Airport
Estimated Arrival Time:
10:30 am
Terminal:
3
Gate:
-
Scheduled Arrival Time: 10:30 am
Disclaimer
The information displayed on this website is gathered from third-party providers with a wide reputation on the sector, which in turn obtain the information from the airlines. This data is provided only for informative purposes. www.seattle-airport.com assumes no responsibility for loss or damage as a result of relying on information posted here. Please contact your airline to verify flight status.

Codeshare Flights

This flight is shared with other airlines, this means that these other flights are the same:

- AF3607 - Air France

- KL6021 - KLM Royal Dutch Airlines

- SK3986 - SAS Scandinavian Airlines

- VS4037 - Virgin Atlantic

Additional Information

Which is the frequency of flight DL20?
The flight DL20 is scheduled to flight on daily basis.

Which is the distance of flight DL20?
The distance between the two airports is 4788 miles.

Which is the flight time of flight DL20?
The scheduled flight time gate to gate is: 09:42 hours.
The real flight time gate to gate on average is: 09:22 hours.

Are the departure airport and arrival airport at the same Time Zone?
No, each airport is in a different timezone. The times shown above, are presented in the local time of each respective airport.
Current Time in Seattle: 2025-12-27 00:13:07
Current Time in London: 2025-12-27 08:13:07

Alternative Flights

The following airlines serves the same route between Seattle and London:

British Airways
- Flight Number: BA48. (On Time performance: 57 - Average Delay: 20 minutes)
- Flight Number: BA52. (On Time performance: 84 - Average Delay: 7 minutes)

Virgin Atlantic
- Flight Number: VS106. (On Time performance: 92 - Average Delay: 5 minutes)

Punctuality and delays

We have gathered data from recent months and present below an analysis of how timely the flights have been.

In terms of On-Time Performance, by analyzing the flight data from the last three months, spanning from September 24, 2025 to December 23, 2025, we have obtained these figures.
Total number of flights: 91
On Time: 68 ( 75 % )
Moderate Delay: 11 ( 12 % )
Significant Delay: 9 ( 10 % )
Major Delay: 2 ( 2 % )
Canceled: 0 ( 0 % )
Diverted: 1 ( 1 % )

Average Delay: 5 minutes.
Delays analyzed by Weekday: We have gathered available data from last six months, spanning from June 24, 2025 to December 23, 2025. Next, you can observe the results broken down by day of the week: number of flights analyzed, on-time performance per day, and average delay per day.

Delays analyzed by Month: We have gathered available data from last twelve closed months, spanning from December 04, 2024 to November 30, 2025. Next, you can observe the results broken down by month: number of flights analyzed, on-time performance per month, and average delay per month.

Last Past Flights DL20

Date
Departure
Arrival
Duration
Aircraft
Status
Saturday
27 December
10:00 pm
Seattle (SEA)
03:54 pm
London (LHR)
09h 54min
Airbus A330-20
Airbus A330-20
Friday
26 December
04:50 pm
Seattle (SEA)
11:02 am
London (LHR)
10h 12min
Airbus A330-20
Airbus A330-20
Landed - Delayed
Thursday
25 December
04:54 pm
Seattle (SEA)
10:36 am
London (LHR)
09h 42min
Airbus A330-20
Airbus A330-20
Landed - On-time
Wednesday
24 December
05:21 pm
Seattle (SEA)
10:47 am
London (LHR)
09h 26min
Airbus A330-20
Airbus A330-20
Landed - Delayed
Tuesday
23 December
04:40 pm
Seattle (SEA)
10:04 am
London (LHR)
09h 24min
Airbus A330-20
Airbus A330-20
Landed - On-time
Monday
22 December
05:46 pm
Seattle (SEA)
11:11 am
London (LHR)
09h 25min
Airbus A330-20
Airbus A330-20
Landed - Delayed
Sunday
21 December
04:45 pm
Seattle (SEA)
10:17 am
London (LHR)
09h 32min
Airbus A330-20
Airbus A330-20
Landed - On-time
Saturday
20 December
04:45 pm
Seattle (SEA)
10:07 am
London (LHR)
09h 22min
Airbus A330-20
Airbus A330-20
Landed - On-time
Friday
19 December
04:43 pm
Seattle (SEA)
10:04 am
London (LHR)
09h 21min
Airbus A330-20
Airbus A330-20
Landed - On-time
Thursday
18 December
04:53 pm
Seattle (SEA)
10:27 am
London (LHR)
09h 34min
Airbus A330-20
Airbus A330-20
Landed - On-time