$165+ Cheap flights from Seattle (SEA) to Delaware
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/7. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ILG
Jun 26 — Jul 31
Round-trip
1 adult, Economy
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Find cheap flights from Seattle to Delaware with Cheapflights
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Cheapest flights from Seattle to DelawareExplore the most affordable flight options available from Seattle to Delaware. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 27, 2026.
Explore the most affordable flight options available from Seattle to Delaware. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 27, 2026.
This Delta deal was found by Cheapflights users on 5/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/119:29 pm
SEA
- PHL
Nonstop5h 11m
Delta
Tue 8/187:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/27![Delta logo]()
$329
This American Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/2510:35 pm
SEA
- PHL
Nonstop5h 12m
American Airlines
Fri 7/37:35 pm
PHL
- SEA
Nonstop6h 21m
American Airlines
Deal found 5/23![American Airlines logo]()
$330
This Alaska Airlines deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/128:32 am
SEA
- PHL
Nonstop5h 17m
Alaska Airlines
Sat 11/144:25 pm
PHL
- SEA
1 stop9h 09m
Alaska Airlines
Deal found 5/24![Alaska Airlines logo]()
$338
This Delta deal was found by Cheapflights users on 5/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/115:10 am
SEA
- PHL
1 stop8h 23m
Delta
Wed 8/197:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/27![Delta logo]()
$339
This American Airlines deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/311:56 pm
SEA
- PHL
1 stop6h 52m
American Airlines
Tue 7/77:35 pm
PHL
- SEA
Nonstop6h 21m
American Airlines
Deal found 5/25![American Airlines logo]()
$343
This Delta deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/1211:53 pm
SEA
- PHL
1 stop7h 47m
Delta
Sat 11/1410:21 am
PHL
- SEA
1 stop11h 38m
Delta
Deal found 5/24![Delta logo]()
$348
This Alaska Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/179:25 pm
SEA
- PHL
Nonstop5h 15m
Alaska Airlines
Wed 10/217:00 am
PHL
- SEA
Nonstop5h 55m
Alaska Airlines
Deal found 5/26![Alaska Airlines logo]()
$353
This Southwest deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/156:40 am
SEA
- PHL
2 stops11h 15m
Southwest
Thu 9/174:05 pm
PHL
- SEA
1 stop7h 40m
Southwest
Deal found 5/26![Southwest logo]()
$354
This American Airlines deal was found by Cheapflights users on 5/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2410:35 pm
SEA
- PHL
Nonstop5h 12m
American Airlines
Mon 6/297:35 pm
PHL
- SEA
Nonstop6h 23m
American Airlines
Deal found 5/27![American Airlines logo]()
$357
This American Airlines deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/312:39 pm
SEA
- PHL
Nonstop5h 26m
American Airlines
Sat 7/117:35 pm
PHL
- SEA
Nonstop6h 21m
American Airlines
Deal found 5/24![American Airlines logo]()
$358
This United Airlines deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2412:50 pm
SEA
- PHL
1 stop7h 40m
United Airlines
Tue 7/216:00 am
PHL
- SEA
1 stop9h 34m
United Airlines
Deal found 5/24![United Airlines logo]()
$359
This American Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/228:10 am
SEA
- SBY
1 stop11h 48m
American Airlines
Sat 8/296:41 am
SBY
- SEA
1 stop17h 16m
American Airlines
Deal found 5/23![American Airlines logo]()
$686
Best flights from Seattle to DelawareDiscover carefully curated flight deals from Seattle to Delaware that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 27, 2026.
Discover carefully curated flight deals from Seattle to Delaware that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated May 27, 2026.
This Delta deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/209:29 pm
SEA
- PHL
Nonstop5h 11m
Delta
Tue 8/257:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/24![Delta logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 5/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/269:27 pm
SEA
- PHL
Nonstop5h 13m
Alaska Airlines
Sat 8/294:48 pm
PHL
- SEA
1 stop8h 51m
Alaska Airlines
Deal found 5/22![Alaska Airlines logo]()
$363
This Southwest deal was found by Cheapflights users on 5/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/78:20 pm
SEA
- PHL
2 stops11h 55m
Southwest
Sat 8/296:30 am
PHL
- SEA
2 stops10h 50m
Southwest
Deal found 5/22![Southwest logo]()
$389
This Delta deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/119:29 pm
SEA
- PHL
Nonstop5h 11m
Delta
Tue 8/187:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/26![Delta logo]()
$329
This American Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/225:15 am
SEA
- SBY
1 stop8h 00m
American Airlines
Sat 8/296:41 am
SBY
- SEA
2 stops10h 51m
American Airlines
Deal found 5/23![American Airlines logo]()
$710
This Delta deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/199:29 pm
SEA
- PHL
Nonstop5h 11m
Delta
Sun 8/237:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/25![Delta logo]()
$329
This Delta deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/299:20 pm
SEA
- PHL
Nonstop5h 09m
Delta
Thu 8/67:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/24![Delta logo]()
$329
This Delta deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/297:16 am
SEA
- PHL
1 stop9h 42m
Delta
Tue 9/17:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/25![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1011:59 pm
SEA
- PHL
1 stop7h 48m
Delta
Sun 8/163:58 pm
PHL
- SEA
1 stop10h 59m
Delta
Deal found 5/24![Delta logo]()
$349
This Delta deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/189:10 am
SEA
- PHL
1 stop10h 04m
Delta
Sun 9/205:45 am
PHL
- SEA
1 stop7h 54m
Delta
Deal found 5/24![Delta logo]()
$349
This Delta deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/125:30 am
SEA
- PHL
1 stop9h 11m
Delta
Mon 7/137:05 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 5/26![Delta logo]()
$430
This American Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/138:15 am
SEA
- SBY
1 stop11h 55m
American Airlines
Tue 6/236:40 am
SBY
- SEA
1 stop19h 18m
American Airlines
Deal found 5/23![American Airlines logo]()
$780
This Delta deal was found by Cheapflights users on 5/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/155:59 pm
SEA
- PHL
1 stop9h 09m
Delta
Fri 7/36:45 pm
PHL
- SEA
Nonstop6h 14m
Delta
Deal found 5/22![Delta logo]()
$433
This Delta deal was found by Cheapflights users on 5/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/155:59 pm
SEA
- PHL
1 stop9h 09m
Delta
Wed 6/246:45 pm
PHL
- SEA
Nonstop6h 14m
Delta
Deal found 5/22![Delta logo]()
$433
This American Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/106:20 am
SEA
- SBY
2 stops11h 10m
American Airlines
Sun 6/146:00 am
SBY
- SEA
1 stop9h 10m
American Airlines
Deal found 5/26![American Airlines logo]()
$958
This American Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/212:39 pm
SEA
- SBY
1 stop7h 19m
American Airlines
Tue 7/74:33 pm
SBY
- SEA
1 stop9h 27m
American Airlines
Deal found 5/26![American Airlines logo]()
$992
This American Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/311:56 pm
SEA
- SBY
2 stops14h 18m
American Airlines
Tue 7/76:00 am
SBY
- SEA
2 stops18h 35m
American Airlines
Deal found 5/26![American Airlines logo]()
$1,012
This American Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/28:20 am
SEA
- SBY
1 stop11h 38m
American Airlines
Mon 7/66:41 am
SBY
- SEA
1 stop19h 15m
American Airlines
Deal found 5/26![American Airlines logo]()
$1,025
Last-minute flights from Seattle to DelawareDiscover last-minute flight deals from Seattle to Delaware. Data last updated May 27, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Delaware. Data last updated May 27, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/287:00 am
SEA
- PHL
1 stop7h 42m
United Airlines
Fri 5/296:00 am
PHL
- SEA
1 stop8h 38m
United Airlines
Deal found 5/26![United Airlines logo]()
$349
This American Airlines deal was found by Cheapflights users on 5/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/2812:46 pm
SEA
- PHL
Nonstop5h 22m
American Airlines
Sat 6/63:50 pm
PHL
- SEA
1 stop10h 09m
American Airlines
Deal found 5/27![American Airlines logo]()
$367
This American Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/138:15 am
SEA
- SBY
1 stop11h 55m
American Airlines
Tue 6/236:40 am
SBY
- SEA
1 stop19h 18m
American Airlines
Deal found 5/23![American Airlines logo]()
$780
This CheapOair deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/157:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Wed 6/1711:00 am
PHL
- SEA
1 stop26h 35m
Frontier
Deal found 5/25![Frontier logo]()
$380
This American Airlines deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/188:10 am
SEA
- PHL
Nonstop5h 24m
American Airlines
Wed 6/248:36 am
PHL
- SEA
Nonstop6h 10m
American Airlines
Deal found 5/25![American Airlines logo]()
$373
This American Airlines deal was found by Cheapflights users on 5/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2410:35 pm
SEA
- PHL
Nonstop5h 12m
American Airlines
Mon 6/297:35 pm
PHL
- SEA
Nonstop6h 23m
American Airlines
Deal found 5/27![American Airlines logo]()
$357
This United Airlines deal was found by Cheapflights users on 5/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2412:50 pm
SEA
- PHL
1 stop7h 40m
United Airlines
Tue 7/216:00 am
PHL
- SEA
1 stop9h 34m
United Airlines
Deal found 5/24![United Airlines logo]()
$359
This United Airlines deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2412:50 pm
SEA
- PHL
1 stop7h 40m
United Airlines
Mon 6/296:23 pm
PHL
- SEA
1 stop9h 52m
United Airlines
Deal found 5/25![United Airlines logo]()
$376
This United Airlines deal was found by Cheapflights users on 5/22. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2412:50 pm
SEA
- PHL
1 stop7h 40m
United Airlines
Thu 7/96:23 pm
PHL
- SEA
1 stop9h 52m
United Airlines
Deal found 5/22![United Airlines logo]()
$377
This American Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/2510:35 pm
SEA
- PHL
Nonstop5h 12m
American Airlines
Fri 7/37:35 pm
PHL
- SEA
Nonstop6h 21m
American Airlines
Deal found 5/23![American Airlines logo]()
$330
This United Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/251:55 pm
SEA
- PHL
1 stop8h 02m
United Airlines
Sat 7/46:00 am
PHL
- SEA
1 stop8h 38m
United Airlines
Deal found 5/26![United Airlines logo]()
$370
This Delta deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/307:20 am
SEA
- PHL
1 stop8h 17m
Delta
Sat 7/46:45 pm
PHL
- SEA
Nonstop6h 14m
Delta
Deal found 5/25![Delta logo]()
$339
One-way flights from Seattle to DelawareSearch for one-way flight options from Seattle to Delaware. Find affordable one-way fares based on user searches. Data last updated May 27, 2026.
Search for one-way flight options from Seattle to Delaware. Find affordable one-way fares based on user searches. Data last updated May 27, 2026.
This American Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/3010:35 pm
SEA
- PHL
Nonstop5h 13m
American Airlines
Deal found 5/26![American Airlines logo]()
$165
This Kiwi.com deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/308:53 pm
SEA
- PHL
2 stops16h 55m
Multiple Airlines
Deal found 5/23![Multiple Airlines logo]()
$167
This Delta deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/305:59 pm
SEA
- PHL
1 stop9h 16m
Delta
Deal found 5/26![Delta logo]()
$175
This United Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/11:55 pm
SEA
- PHL
1 stop8h 02m
United Airlines
Deal found 5/23![United Airlines logo]()
$179
This Southwest deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/511:00 pm
SEA
- PHL
1 stop11h 15m
Southwest
Deal found 5/26![Southwest logo]()
$180
This Frontier deal was found by Cheapflights users on 5/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/17:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Deal found 5/25![Frontier logo]()
$181
This United Airlines deal was found by Cheapflights users on 5/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/2412:50 pm
SEA
- PHL
1 stop7h 40m
United Airlines
Deal found 5/26![United Airlines logo]()
$185
This Kiwi.com deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/228:13 pm
SEA
- PHL
2 stops41h 35m
Multiple Airlines
Deal found 5/23![Multiple Airlines logo]()
$186
This United Airlines deal was found by Cheapflights users on 5/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/210:29 am
SEA
- PHL
1 stop11h 54m
United Airlines
Deal found 5/23![United Airlines logo]()
$192
This Kiwi.com deal was found by Cheapflights users on 5/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/2211:59 pm
SEA
- SBY
3 stops42h 03m
Multiple Airlines
Deal found 5/27![Multiple Airlines logo]()
$462
This American Airlines deal was found by Cheapflights users on 5/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/229:35 pm
SEA
- SBY
1 stop10h 27m
American Airlines
Deal found 5/27![American Airlines logo]()
$709
Find flight deals from Seattle to Delaware
Keep the following information in mind while searching for Seattle to Delaware flight deals. Data was last updated May 27, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $329 (Delta) |
One-way from | $165 (American Airlines) |
Popular in | December |
Cheapest in | October |
Average price | $435 |
Cheapflights Fare Finder
Customize your flight search to find flights from Seattle to Delaware that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 27, 2026.
Use the filters below to find and compare flights from Seattle to Delaware that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 8/20
9:29 pm-5:40 am
Nonstop5h 11m
Philadelphia
Tue 8/25
7:00 am-9:56 am
Nonstop5h 56m
$329
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 8/11
9:29 pm-5:40 am
Nonstop5h 11m
Philadelphia
Tue 8/18
7:00 am-9:56 am
Nonstop5h 56m
$329
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 8/19
9:29 pm-5:40 am
Nonstop5h 11m
Philadelphia
Sun 8/23
7:00 am-9:56 am
Nonstop5h 56m
$329
Quickest round-trip
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 7/29
9:20 pm-5:29 am
Nonstop5h 09m
Philadelphia
Thu 8/6
7:00 am-9:56 am
Nonstop5h 56m
$329
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Sat 8/29
7:16 am-7:58 pm
1 stop9h 42m
Philadelphia
Tue 9/1
7:00 am-9:56 am
Nonstop5h 56m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Mon 8/10
11:59 pm-10:47 am
1 stop7h 48m
Philadelphia
Sun 8/16
3:58 pm-11:57 pm
1 stop10h 59m
$349
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 9/18
9:10 am-10:14 pm
1 stop10h 04m
Philadelphia
Sun 9/20
5:45 am-10:39 am
1 stop7h 54m
$349
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 8/26
9:27 pm-5:40 am
Nonstop5h 13m
Philadelphia
Sat 8/29
4:48 pm-10:39 pm
1 stop8h 51m
$363
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 8/7
8:20 pm-11:15 am
2 stops11h 55m
Philadelphia
Sat 8/29
6:30 am-2:20 pm
2 stops10h 50m
$389
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 6/12
5:30 am-5:41 pm
1 stop9h 11m
Philadelphia
Mon 7/13
7:05 am-10:01 am
Nonstop5h 56m
$430
Showing 1-10 of 31 resultsSorted by cheapest first
Best time to book a flight from Seattle to Delaware
Have a flexible travel schedule? Discover the best time to fly to Delaware from Seattle with our price prediction graph.
SEA-PHL
SEA-SBY
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Seattle to Delaware
SEA-USDE
SEA-PHL
SEA-SBY
No data available for this route at this time. Please check back soon.
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