$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 9/8. Fares are subject to change and may not be available on all flights or dates of travel.
SEA ā ILG
Aug 21 ā Aug 281
Round-trip
1 adult, Economy
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Find cheap flights from Seattle to Delaware with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click āFind dealsā2. Select your favorite providers
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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 July 22, 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 July 22, 2026.
This Delta deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 9/19:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Tue 9/157:05 am
PHL
- SEA
Nonstop5h 51m
Delta
Deal found 7/17![Delta logo]()
$329
This Justfly.com deal was found by Cheapflights users on 7/19. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Justfly.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 10/2011:55 pm
SEA
- PHL
1 stop11h 35m
Multiple Airlines
Sat 11/74:25 pm
PHL
- SEA
1 stop9h 09m
Multiple Airlines
Deal found 7/19![Multiple Airlines logo]()
$330
This Kiwi.com deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/147:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Fri 8/214:45 pm
PHL
- SEA
2 stops43h 34m
Frontier
Deal found 7/20![Frontier logo]()
$331
This Kiwi.com deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 9/17:07 pm
SEA
- PHL
1 stop7h 32m
Multiple Airlines
Sun 9/207:00 am
PHL
- SEA
Nonstop5h 51m
Multiple Airlines
Deal found 7/18![Multiple Airlines logo]()
$332
This Expedia deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Expedia is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/188:53 pm
SEA
- PHL
1 stop30h 37m
Multiple Airlines
Tue 8/256:59 pm
PHL
- SEA
Nonstop5h 52m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$333
This Kiwi.com deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 9/17:07 pm
SEA
- PHL
1 stop7h 32m
Multiple Airlines
Mon 9/217:00 am
PHL
- SEA
Nonstop5h 51m
Multiple Airlines
Deal found 7/18![Multiple Airlines logo]()
$334
This Kiwi.com deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Mon 8/317:06 pm
SEA
- PHL
1 stop7h 33m
Multiple Airlines
Wed 9/237:00 am
PHL
- SEA
Nonstop5h 51m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$335
This CheapOair deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure CheapOair is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Thu 8/68:53 pm
SEA
- PHL
1 stop30h 07m
Frontier
Sat 8/1511:06 am
PHL
- SEA
1 stop26h 58m
Frontier
Deal found 7/20![Frontier logo]()
$336
This Kiwi.com deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Wed 9/27:06 pm
SEA
- PHL
1 stop7h 33m
Multiple Airlines
Mon 9/217:00 am
PHL
- SEA
Nonstop5h 51m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$337
This Kiwi.com deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/258:53 pm
SEA
- PHL
1 stop30h 37m
Multiple Airlines
Thu 8/276:59 pm
PHL
- SEA
Nonstop5h 52m
Multiple Airlines
Deal found 7/17![Multiple Airlines logo]()
$338
This Delta deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Thu 9/37:50 pm
SEA
- PHL
1 stop7h 15m
Delta
Wed 9/237:05 am
PHL
- SEA
Nonstop5h 51m
Delta
Deal found 7/20![Delta logo]()
$339
This Kiwi.com deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 7/218:13 pm
SEA
- PHL
1 stop30h 47m
Frontier
Mon 7/278:37 pm
PHL
- SEA
1 stop15h 40m
Frontier
Deal found 7/18![Frontier logo]()
$340
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 July 22, 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 July 22, 2026.
This Alaska Airlines deal was found by Cheapflights users on 7/21. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Alaska Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Wed 10/79:19 am
SEA
- PHL
Nonstop5h 19m
Alaska Airlines
Sun 10/117:02 am
PHL
- SEA
Nonstop5h 53m
Alaska Airlines
Deal found 7/21![Alaska Airlines logo]()
$329
This Delta deal was found by Cheapflights users on 7/21. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 10/911:05 pm
SEA
- PHL
1 stop6h 40m
Delta
Sun 10/117:00 am
PHL
- SEA
Nonstop5h 58m
Delta
Deal found 7/21![Delta logo]()
$349
This Southwest deal was found by Cheapflights users on 7/19. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Southwest is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 9/118:20 pm
SEA
- PHL
2 stops11h 55m
Southwest
Fri 9/182:05 pm
PHL
- SEA
2 stops9h 40m
Southwest
Deal found 7/19![Southwest logo]()
$393
This United Airlines deal was found by Cheapflights users on 7/19. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure United Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Wed 8/126:15 pm
SEA
- PHL
2 stops12h 28m
United Airlines
Wed 8/196:00 am
PHL
- SEA
1 stop11h 24m
United Airlines
Deal found 7/19![United Airlines logo]()
$398
This American Airlines deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure American Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Sat 9/128:20 am
SEA
- SBY
1 stop11h 39m
American Airlines
Sat 9/196:41 am
SBY
- SEA
1 stop19h 16m
American Airlines
Deal found 7/20![American Airlines logo]()
$686
This Delta deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/116:00 am
SEA
- PHL
1 stop8h 34m
Delta
Tue 8/187:05 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 7/18![Delta logo]()
$378
This Alaska Airlines deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Alaska Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 10/69:19 am
SEA
- PHL
Nonstop5h 19m
Alaska Airlines
Wed 10/77:02 am
PHL
- SEA
Nonstop5h 53m
Alaska Airlines
Deal found 7/18![Alaska Airlines logo]()
$389
This Delta deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/119:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Sun 8/235:45 am
PHL
- SEA
1 stop8h 15m
Delta
Deal found 7/17![Delta logo]()
$378
This Southwest deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Southwest is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/186:40 am
SEA
- PHL
2 stops8h 20m
Southwest
Mon 8/2412:45 pm
PHL
- SEA
2 stops11h 00m
Southwest
Deal found 7/20![Southwest logo]()
$422
This Delta deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/79:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Tue 8/117:05 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 7/17![Delta logo]()
$407
This Southwest deal was found by Cheapflights users on 7/21. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Southwest is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/288:20 pm
SEA
- PHL
2 stops11h 55m
Southwest
Fri 9/410:20 am
PHL
- SEA
2 stops10h 15m
Southwest
Deal found 7/21![Southwest logo]()
$464
This Delta deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Mon 8/179:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Tue 8/257:20 am
PHL
- SEA
1 stop8h 39m
Delta
Deal found 7/18![Delta logo]()
$413
This American Airlines deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure American Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/218:10 am
SEA
- SBY
1 stop11h 48m
American Airlines
Tue 8/256:41 am
SBY
- SEA
1 stop19h 15m
American Airlines
Deal found 7/20![American Airlines logo]()
$779
This American Airlines deal was found by Cheapflights users on 7/21. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure American Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Wed 8/56:25 am
SEA
- SBY
1 stop10h 46m
American Airlines
Sun 8/96:41 am
SBY
- SEA
1 stop8h 09m
American Airlines
Deal found 7/21![American Airlines logo]()
$952
Last-minute flights from Seattle to DelawareDiscover last-minute flight deals from Seattle to Delaware. Data last updated July 22, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Delaware. Data last updated July 22, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 7/218:13 pm
SEA
- PHL
1 stop30h 47m
Frontier
Mon 7/278:37 pm
PHL
- SEA
1 stop15h 40m
Frontier
Deal found 7/18![Frontier logo]()
$340
This Kiwi.com deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Thu 7/237:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Wed 7/2911:06 am
PHL
- SEA
1 stop26h 33m
Frontier
Deal found 7/18![Frontier logo]()
$337
This Frontier deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Frontier is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Mon 8/37:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Fri 8/148:37 pm
PHL
- SEA
1 stop15h 27m
Frontier
Deal found 7/20![Frontier logo]()
$332
This Trip.com deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Trip.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Thu 8/68:53 pm
SEA
- PHL
1 stop30h 07m
Frontier
Wed 9/168:44 pm
PHL
- SEA
1 stop30h 43m
Frontier
Deal found 7/17![Frontier logo]()
$334
This CheapOair deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure CheapOair is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Thu 8/68:53 pm
SEA
- PHL
1 stop30h 07m
Frontier
Sat 8/1511:06 am
PHL
- SEA
1 stop26h 58m
Frontier
Deal found 7/20![Frontier logo]()
$336
This Kiwi.com deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Wed 8/127:06 pm
SEA
- PHL
1 stop13h 43m
Frontier
Sat 8/154:30 pm
PHL
- SEA
2 stops19h 34m
Frontier
Deal found 7/18![Frontier logo]()
$330
This Kiwi.com deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/147:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Fri 8/214:45 pm
PHL
- SEA
2 stops43h 34m
Frontier
Deal found 7/20![Frontier logo]()
$331
This Expedia deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Expedia is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/188:53 pm
SEA
- PHL
1 stop30h 37m
Multiple Airlines
Tue 8/256:59 pm
PHL
- SEA
Nonstop5h 52m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$333
This Kiwi.com deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/258:53 pm
SEA
- PHL
1 stop30h 37m
Multiple Airlines
Thu 8/276:59 pm
PHL
- SEA
Nonstop5h 52m
Multiple Airlines
Deal found 7/17![Multiple Airlines logo]()
$338
This Alaska Airlines deal was found by Cheapflights users on 7/21. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Alaska Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/289:27 pm
SEA
- PHL
Nonstop5h 13m
Alaska Airlines
Sat 9/57:02 am
PHL
- SEA
Nonstop5h 51m
Alaska Airlines
Deal found 7/21![Alaska Airlines logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 7/21. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Alaska Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/289:27 pm
SEA
- PHL
Nonstop5h 13m
Alaska Airlines
Tue 9/84:48 pm
PHL
- SEA
1 stop8h 51m
Alaska Airlines
Deal found 7/21![Alaska Airlines logo]()
$339
This Kiwi.com deal was found by Cheapflights users on 7/20. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Mon 8/317:06 pm
SEA
- PHL
1 stop7h 33m
Multiple Airlines
Wed 9/237:00 am
PHL
- SEA
Nonstop5h 51m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$335
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 July 22, 2026.
Search for one-way flight options from Seattle to Delaware. Find affordable one-way fares based on user searches. Data last updated July 22, 2026.
This Delta deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 9/89:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Deal found 7/17![Delta logo]()
$165
This American Airlines deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure American Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/219:58 pm
SEA
- PHL
Nonstop5h 18m
American Airlines
Deal found 7/17![American Airlines logo]()
$166
This Frontier deal was found by Cheapflights users on 7/18. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Frontier is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Wed 8/127:06 pm
SEA
- PHL
1 stop13h 43m
Frontier
Deal found 7/18![Frontier logo]()
$167
This Kiwi.com deal was found by Cheapflights users on 7/19. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Mon 10/197:41 pm
SEA
- PHL
1 stop30h 55m
Frontier
Deal found 7/19![Frontier logo]()
$168
This United Airlines deal was found by Cheapflights users on 7/19. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure United Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Thu 9/31:57 pm
SEA
- PHL
1 stop8h 02m
United Airlines
Deal found 7/19![United Airlines logo]()
$169
This Delta deal was found by Cheapflights users on 7/21. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 9/19:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Deal found 7/21![Delta logo]()
$170
This CheapOair deal was found by Cheapflights users on 7/19. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure CheapOair is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/48:13 pm
SEA
- PHL
1 stop30h 47m
Frontier
Deal found 7/19![Frontier logo]()
$172
This United Airlines deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure United Airlines is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/281:57 pm
SEA
- PHL
1 stop8h 02m
United Airlines
Deal found 7/17![United Airlines logo]()
$173
This Southwest deal was found by Cheapflights users on 7/19. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Southwest is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Wed 9/27:10 am
SEA
- PHL
2 stops10h 25m
Southwest
Deal found 7/19![Southwest logo]()
$174
This Delta deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Delta is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Thu 9/175:50 pm
SEA
- PHL
1 stop9h 15m
Delta
Deal found 7/17![Delta logo]()
$175
This Kiwi.com deal was found by Cheapflights users on 7/17. Clicking the āPick Datesā button in this card will allow you to select your dates and further customize your flight criteria. From there, click āFind dealsā, make sure Kiwi.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/182:37 pm
SEA
- PHL
2 stops18h 49m
Frontier
Deal found 7/17![Frontier logo]()
$176
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 July 22, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $329 (Alaska Airlines) |
One-way from | $165 (Delta) |
Popular in | December |
Cheapest in | October |
Average price | $417 |
Cheapflights Fare Finder
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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 July 22, 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
Quickest round-trip
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 10/7
9:19 am-5:38 pm
Nonstop5h 19m
Philadelphia
Sun 10/11
7:02 am-9:55 am
Nonstop5h 53m
$329
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 10/9
11:05 pm-8:45 am
1 stop6h 40m
Philadelphia
Sun 10/11
7:00 am-9:58 am
Nonstop5h 58m
$349
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 8/11
6:00 am-5:34 pm
1 stop8h 34m
Philadelphia
Tue 8/18
7:05 am-10:01 am
Nonstop5h 56m
$378
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 8/11
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Sun 8/23
5:45 am-11:00 am
1 stop8h 15m
$378
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 10/6
9:19 am-5:38 pm
Nonstop5h 19m
Philadelphia
Wed 10/7
7:02 am-9:55 am
Nonstop5h 53m
$389
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 9/11
8:20 pm-11:15 am
2 stops11h 55m
Philadelphia
Fri 9/18
2:05 pm-8:45 pm
2 stops9h 40m
$393
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 8/12
6:15 pm-9:43 am
2 stops12h 28m
Philadelphia
Wed 8/19
6:00 am-2:24 pm
1 stop11h 24m
$398
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 8/7
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Tue 8/11
7:05 am-10:01 am
Nonstop5h 56m
$407
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Mon 8/17
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Tue 8/25
7:20 am-12:59 pm
1 stop8h 39m
$413
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 8/18
6:40 am-6:00 pm
2 stops8h 20m
Philadelphia
Mon 8/24
12:45 pm-8:45 pm
2 stops11h 00m
$422
Showing 1-10 of 26 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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