$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 8/19. Fares are subject to change and may not be available on all flights or dates of travel.
SEA ā ILG
Sep 2 ā Sep 91
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 August 3, 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 August 3, 2026.
This Priceline deal was found by Cheapflights users on 7/29. 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 Priceline 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
Multiple Airlines
Thu 9/37:00 am
PHL
- SEA
1 stop11h 28m
Multiple Airlines
Deal found 7/29![Multiple Airlines logo]()
$330
This Kiwi.com deal was found by Cheapflights users on 7/28. 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 9/47:06 pm
SEA
- PHL
2 stops22h 22m
Frontier
Mon 9/78:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/28![Frontier logo]()
$331
This Kiwi.com deal was found by Cheapflights users on 7/29. 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 8/197:06 pm
SEA
- PHL
2 stops23h 14m
Frontier
Sun 8/238:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/29![Frontier logo]()
$332
This Expedia deal was found by Cheapflights users on 7/31. 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.
Wed 8/198:53 pm
SEA
- PHL
1 stop30h 37m
Multiple Airlines
Wed 9/94:48 pm
PHL
- SEA
1 stop8h 51m
Multiple Airlines
Deal found 7/31![Multiple Airlines logo]()
$333
This Kiwi.com deal was found by Cheapflights users on 7/29. 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 8/217:06 pm
SEA
- PHL
2 stops18h 31m
Frontier
Sun 8/238:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/29![Frontier logo]()
$334
This Kiwi.com deal was found by Cheapflights users on 8/2. 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 8/262:37 pm
SEA
- PHL
1 stop12h 02m
Frontier
Wed 9/98:41 am
PHL
- SEA
2 stops28h 01m
Frontier
Deal found 8/2![Frontier logo]()
$335
This CheapOair deal was found by Cheapflights users on 7/31. 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 9/17:07 pm
SEA
- PHL
1 stop7h 32m
Multiple Airlines
Tue 9/153:57 pm
PHL
- SEA
1 stop9h 40m
Multiple Airlines
Deal found 7/31![Multiple Airlines logo]()
$336
This Flightnetwork deal was found by Cheapflights users on 7/29. 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 Flightnetwork is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/412:35 pm
SEA
- PHL
1 stop20h 14m
Frontier
Mon 8/108:37 pm
PHL
- SEA
1 stop15h 27m
Frontier
Deal found 7/29![Frontier logo]()
$337
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 9/79:36 pm
SEA
- PHL
1 stop29h 54m
Multiple Airlines
Tue 9/157:00 am
PHL
- SEA
Nonstop5h 51m
Multiple Airlines
Deal found 7/30![Multiple Airlines logo]()
$338
This CheapOair deal was found by Cheapflights users on 7/28. 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.
Mon 8/177:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Mon 8/248:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/28![Frontier logo]()
$339
This Southwest deal was found by Cheapflights users on 7/31. 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.
Sun 9/65:10 am
SEA
- PHL
2 stops15h 55m
Southwest
Tue 9/810:45 am
PHL
- SEA
1 stop10h 10m
Southwest
Deal found 7/31![Southwest logo]()
$340
This Kiwi.com deal was found by Cheapflights users on 7/31. 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 10/29:27 pm
SEA
- PHL
Nonstop5h 13m
Multiple Airlines
Thu 10/228:44 pm
PHL
- SEA
1 stop16h 07m
Multiple Airlines
Deal found 7/31![Multiple Airlines logo]()
$341
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 August 3, 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 August 3, 2026.
This Southwest deal was found by Cheapflights users on 7/29. 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.
Thu 10/295:50 am
SEA
- PHL
2 stops10h 45m
Southwest
Mon 11/21:50 pm
PHL
- SEA
2 stops12h 10m
Southwest
Deal found 7/29![Southwest logo]()
$339
This Delta deal was found by Cheapflights users on 8/1. 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 10/227:55 pm
SEA
- PHL
1 stop7h 10m
Delta
Sun 10/257:00 am
PHL
- SEA
Nonstop5h 58m
Delta
Deal found 8/1![Delta logo]()
$369
This Alaska Airlines deal was found by Cheapflights users on 7/31. 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 9/229:33 am
SEA
- PHL
Nonstop5h 23m
Alaska Airlines
Wed 9/236:59 pm
PHL
- SEA
Nonstop5h 52m
Alaska Airlines
Deal found 7/31![Alaska Airlines logo]()
$419
This United Airlines deal was found by Cheapflights users on 7/28. 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 9/246:05 pm
SEA
- PHL
2 stops12h 38m
United Airlines
Thu 10/19:34 am
PHL
- SEA
2 stops14h 03m
United Airlines
Deal found 7/28![United Airlines logo]()
$431
This Southwest deal was found by Cheapflights users on 7/28. 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.
Thu 9/105:15 am
SEA
- PHL
1 stop7h 45m
Southwest
Sun 9/135:05 pm
PHL
- SEA
1 stop9h 10m
Southwest
Deal found 7/28![Southwest logo]()
$345
This American Airlines deal was found by Cheapflights users on 7/30. 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.
Thu 9/106:40 am
SEA
- SBY
1 stop9h 22m
American Airlines
Fri 9/116:41 am
SBY
- SEA
1 stop7h 59m
American Airlines
Deal found 7/30![American Airlines logo]()
$714
This Southwest deal was found by Cheapflights users on 7/31. 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.
Mon 9/1411:05 pm
SEA
- PHL
1 stop9h 30m
Southwest
Mon 9/214:05 pm
PHL
- SEA
1 stop9h 55m
Southwest
Deal found 7/31![Southwest logo]()
$347
This United Airlines deal was found by Cheapflights users on 7/29. 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.
Tue 9/19:05 am
SEA
- PHL
2 stops12h 54m
United Airlines
Sat 9/128:30 am
PHL
- SEA
2 stops12h 12m
United Airlines
Deal found 7/29![United Airlines logo]()
$431
This Delta deal was found by Cheapflights users on 7/31. 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 8/219:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Mon 8/247:05 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 7/31![Delta logo]()
$437
This Southwest deal was found by Cheapflights users on 7/31. 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.
Thu 10/2212:10 am
SEA
- PHL
1 stop7h 40m
Southwest
Sun 10/256:45 am
PHL
- SEA
1 stop8h 50m
Southwest
Deal found 7/31![Southwest logo]()
$379
This United Airlines deal was found by Cheapflights users on 7/31. 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.
Tue 9/227:00 am
SEA
- PHL
1 stop7h 54m
United Airlines
Wed 9/239:30 am
PHL
- SEA
1 stop9h 37m
United Airlines
Deal found 7/31![United Airlines logo]()
$457
This Southwest deal was found by Cheapflights users on 7/30. 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.
Sat 8/295:00 am
SEA
- PHL
2 stops10h 20m
Southwest
Sat 9/56:30 am
PHL
- SEA
2 stops10h 50m
Southwest
Deal found 7/30![Southwest logo]()
$412
This American Airlines deal was found by Cheapflights users on 7/30. 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 8/156:25 am
SEA
- SBY
1 stop10h 46m
American Airlines
Wed 8/196:41 am
SBY
- SEA
1 stop8h 09m
American Airlines
Deal found 7/30![American Airlines logo]()
$801
This American Airlines deal was found by Cheapflights users on 7/29. 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.
Thu 8/278:10 am
SEA
- SBY
1 stop11h 48m
American Airlines
Sun 8/306:41 am
SBY
- SEA
1 stop19h 15m
American Airlines
Deal found 7/29![American Airlines logo]()
$880
Last-minute flights from Seattle to DelawareDiscover last-minute flight deals from Seattle to Delaware. Data last updated August 3, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Delaware. Data last updated August 3, 2026 and is based on user searches.
This Flightnetwork deal was found by Cheapflights users on 7/29. 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 Flightnetwork is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Tue 8/412:35 pm
SEA
- PHL
1 stop20h 14m
Frontier
Mon 8/108:37 pm
PHL
- SEA
1 stop15h 27m
Frontier
Deal found 7/29![Frontier logo]()
$337
This Frontier deal was found by Cheapflights users on 7/29. 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.
Thu 8/67:06 pm
SEA
- PHL
1 stop13h 43m
Frontier
Mon 8/108:37 pm
PHL
- SEA
1 stop15h 27m
Frontier
Deal found 7/29![Frontier logo]()
$342
This CheapOair deal was found by Cheapflights users on 7/28. 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.
Mon 8/177:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Mon 8/248:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/28![Frontier logo]()
$339
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 8/187:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Sun 8/238:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/30![Frontier logo]()
$336
This Kiwi.com deal was found by Cheapflights users on 7/29. 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 8/197:06 pm
SEA
- PHL
2 stops23h 14m
Frontier
Sun 8/238:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/29![Frontier logo]()
$332
This Expedia deal was found by Cheapflights users on 7/31. 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.
Wed 8/198:53 pm
SEA
- PHL
1 stop30h 37m
Multiple Airlines
Wed 9/94:48 pm
PHL
- SEA
1 stop8h 51m
Multiple Airlines
Deal found 7/31![Multiple Airlines logo]()
$333
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 8/192:37 pm
SEA
- PHL
1 stop12h 02m
Frontier
Thu 8/278:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/30![Frontier logo]()
$343
This Kiwi.com deal was found by Cheapflights users on 7/29. 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 8/217:06 pm
SEA
- PHL
2 stops18h 31m
Frontier
Sun 8/238:37 pm
PHL
- SEA
1 stop15h 42m
Frontier
Deal found 7/29![Frontier logo]()
$334
This CheapOair deal was found by Cheapflights users on 7/29. 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.
Fri 8/219:29 pm
SEA
- PHL
1 stop30h 01m
Frontier
Mon 8/248:00 am
PHL
- SEA
1 stop29h 39m
Frontier
Deal found 7/29![Frontier logo]()
$341
This Kiwi.com deal was found by Cheapflights users on 8/2. 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 8/262:37 pm
SEA
- PHL
1 stop12h 02m
Frontier
Wed 9/98:41 am
PHL
- SEA
2 stops28h 01m
Frontier
Deal found 8/2![Frontier logo]()
$335
This Priceline deal was found by Cheapflights users on 7/29. 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 Priceline 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
Multiple Airlines
Thu 9/37:00 am
PHL
- SEA
1 stop11h 28m
Multiple Airlines
Deal found 7/29![Multiple Airlines logo]()
$330
This Orbitz deal was found by Cheapflights users on 7/30. 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 Orbitz is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Fri 8/287:06 pm
SEA
- PHL
1 stop7h 33m
Multiple Airlines
Tue 9/86:59 pm
PHL
- SEA
Nonstop5h 52m
Multiple Airlines
Deal found 7/30![Multiple Airlines logo]()
$340
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 August 3, 2026.
Search for one-way flight options from Seattle to Delaware. Find affordable one-way fares based on user searches. Data last updated August 3, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 8/192:37 pm
SEA
- PHL
2 stops21h 52m
Frontier
Deal found 7/30![Frontier logo]()
$165
This Trip.com deal was found by Cheapflights users on 7/29. 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.
Fri 8/211:35 pm
SEA
- PHL
2 stops24h 02m
Frontier
Deal found 7/29![Frontier logo]()
$166
This Southwest deal was found by Cheapflights users on 7/31. 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.
Sun 9/65:10 am
SEA
- PHL
2 stops15h 55m
Southwest
Deal found 7/31![Southwest logo]()
$167
This Kiwi.com deal was found by Cheapflights users on 7/30. 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.
Sun 8/307:06 pm
SEA
- PHL
2 stops22h 22m
Frontier
Deal found 7/30![Frontier logo]()
$168
This Kiwi.com deal was found by Cheapflights users on 7/30. 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.
Sat 9/269:45 pm
SEA
- PHL
2 stops37h 36m
Frontier
Deal found 7/30![Frontier logo]()
$169
This Kiwi.com deal was found by Cheapflights users on 7/30. 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 8/262:37 pm
SEA
- PHL
1 stop12h 02m
Frontier
Deal found 7/30![Frontier logo]()
$170
This Super.com deal was found by Cheapflights users on 7/29. 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 Super.com is selected, and click āCompare selectedā under the list of providers to see comparable flight deals.
Sat 8/158:13 pm
SEA
- PHL
1 stop30h 47m
Frontier
Deal found 7/29![Frontier logo]()
$171
This Frontier deal was found by Cheapflights users on 7/30. 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.
Tue 8/187:06 pm
SEA
- PHL
1 stop7h 33m
Frontier
Deal found 7/30![Frontier logo]()
$173
This United Airlines deal was found by Cheapflights users on 8/2. 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 9/911:00 pm
SEA
- PHL
1 stop8h 02m
United Airlines
Deal found 8/2![United Airlines logo]()
$174
This Kiwi.com deal was found by Cheapflights users on 8/2. 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 9/104:27 pm
SEA
- PHL
2 stops47h 37m
Frontier
Deal found 8/2![Frontier logo]()
$176
This Kiwi.com deal was found by Cheapflights users on 7/29. 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 8/281:35 pm
SEA
- SBY
3 stops26h 51m
Multiple Airlines
Deal found 7/29![Multiple Airlines logo]()
$218
This Kiwi.com deal was found by Cheapflights users on 7/29. 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.
Sat 8/298:53 pm
SEA
- SBY
2 stops42h 54m
Multiple Airlines
Deal found 7/29![Multiple Airlines logo]()
$234
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 August 3, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $330 (Priceline) |
One-way from | $165 (Kiwi.com) |
Popular in | December |
Cheapest in | October |
Average price | $473 |
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 August 3, 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 10/29
5:50 am-7:35 pm
2 stops10h 45m
Philadelphia
Mon 11/2
1:50 pm-11:00 pm
2 stops12h 10m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 9/10
5:15 am-4:00 pm
1 stop7h 45m
Philadelphia
Sun 9/13
5:05 pm-11:15 pm
1 stop9h 10m
$345
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Mon 9/14
11:05 pm-11:35 am
1 stop9h 30m
Philadelphia
Mon 9/21
4:05 pm-11:00 pm
1 stop9h 55m
$347
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 10/22
7:55 pm-6:05 am
1 stop7h 10m
Philadelphia
Sun 10/25
7:00 am-9:58 am
Nonstop5h 58m
$369
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 10/22
12:10 am-10:50 am
1 stop7h 40m
Philadelphia
Sun 10/25
6:45 am-12:35 pm
1 stop8h 50m
$379
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Sat 8/29
5:00 am-6:20 pm
2 stops10h 20m
Philadelphia
Sat 9/5
6:30 am-2:20 pm
2 stops10h 50m
$412
Quickest round-trip
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 9/22
9:33 am-5:56 pm
Nonstop5h 23m
Philadelphia
Wed 9/23
6:59 pm-9:51 pm
Nonstop5h 52m
$419
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 9/24
6:05 pm-9:43 am
2 stops12h 38m
Philadelphia
Thu 10/1
9:34 am-8:37 pm
2 stops14h 03m
$431
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 9/1
9:05 am-12:59 am
2 stops12h 54m
Philadelphia
Sat 9/12
8:30 am-5:42 pm
2 stops12h 12m
$431
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 8/21
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Mon 8/24
7:05 am-10:01 am
Nonstop5h 56m
$437
Showing 1-10 of 30 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
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