$139+ 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 4/4. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ILG
Apr 29 — May 61
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 “Find deals”2. 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 March 30, 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 March 30, 2026.
This CheapOair deal was found by Cheapflights users on 3/28. 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.
Thu 6/183:19 pm
SEA
- PHL
1 stop17h 28m
Frontier
Mon 6/227:50 pm
PHL
- SEA
1 stop25h 36m
Frontier
Deal found 3/28![Frontier logo]()
$281
This Kiwi.com deal was found by Cheapflights users on 3/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:12 pm
SEA
- PHL
2 stops26h 42m
Frontier
Mon 4/208:41 pm
PHL
- SEA
1 stop15h 46m
Frontier
Deal found 3/25![Frontier logo]()
$282
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/117:50 pm
SEA
- PHL
1 stop30h 47m
Frontier
Thu 5/146:43 pm
PHL
- SEA
2 stops18h 39m
Frontier
Deal found 3/26![Frontier logo]()
$283
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/274:20 pm
SEA
- PHL
1 stop10h 14m
Frontier
Mon 5/45:01 am
PHL
- SEA
2 stops13h 04m
Frontier
Deal found 3/26![Frontier logo]()
$284
This Southwest deal was found by Cheapflights users on 3/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/249:00 pm
SEA
- PHL
2 stops10h 35m
Southwest
Tue 4/282:00 pm
PHL
- SEA
2 stops11h 30m
Southwest
Deal found 3/25![Southwest logo]()
$285
This Expedia deal was found by Cheapflights users on 3/27. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/309:07 pm
SEA
- PHL
1 stop29h 06m
Frontier
Mon 5/48:41 pm
PHL
- SEA
1 stop16h 08m
Frontier
Deal found 3/27![Frontier logo]()
$286
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/911:37 am
SEA
- PHL
2 stops21h 48m
Frontier
Tue 5/128:35 pm
PHL
- SEA
1 stop16h 14m
Frontier
Deal found 3/26![Frontier logo]()
$287
This Expedia deal was found by Cheapflights users on 3/29. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/174:20 pm
SEA
- PHL
1 stop10h 14m
Multiple Airlines
Mon 4/207:25 am
PHL
- SEA
Nonstop6h 05m
Multiple Airlines
Deal found 3/29![Multiple Airlines logo]()
$289
This Kiwi.com deal was found by Cheapflights users on 3/27. 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.
Fri 4/2410:11 pm
SEA
- PHL
2 stops28h 24m
Frontier
Fri 5/18:41 pm
PHL
- SEA
1 stop15h 46m
Frontier
Deal found 3/27![Frontier logo]()
$290
This CheapOair deal was found by Cheapflights users on 3/27. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/164:20 pm
SEA
- PHL
1 stop10h 14m
Frontier
Sun 4/198:36 pm
PHL
- SEA
1 stop15h 51m
Frontier
Deal found 3/27![Frontier logo]()
$291
This Kiwi.com deal was found by Cheapflights users on 3/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:12 pm
SEA
- PHL
2 stops12h 41m
Frontier
Wed 4/158:41 pm
PHL
- SEA
1 stop15h 46m
Frontier
Deal found 3/25![Frontier logo]()
$292
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/14:20 pm
SEA
- PHL
1 stop10h 14m
Frontier
Fri 5/88:35 pm
PHL
- SEA
1 stop16h 14m
Frontier
Deal found 3/26![Frontier logo]()
$293
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 March 30, 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 March 30, 2026.
This Delta deal was found by Cheapflights users on 3/29. 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 6/49:20 pm
SEA
- PHL
Nonstop5h 15m
Delta
Sat 6/67:10 am
PHL
- SEA
Nonstop5h 50m
Delta
Deal found 3/29![Delta logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 3/25. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/99:44 pm
SEA
- PHL
Nonstop5h 18m
Alaska Airlines
Wed 5/137:16 pm
PHL
- SEA
Nonstop6h 12m
Alaska Airlines
Deal found 3/25![Alaska Airlines logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 3/26. 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.
Tue 4/219:55 pm
SEA
- PHL
Nonstop5h 10m
Alaska Airlines
Sat 4/257:22 am
PHL
- SEA
Nonstop5h 58m
Alaska Airlines
Deal found 3/26![Alaska Airlines logo]()
$337
This Delta deal was found by Cheapflights users on 3/25. 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.
Fri 9/187:35 pm
SEA
- PHL
1 stop7h 08m
Delta
Sun 9/207:05 am
PHL
- SEA
Nonstop5h 59m
Delta
Deal found 3/25![Delta logo]()
$339
This American Airlines deal was found by Cheapflights users on 3/28. 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 5/278:10 am
SEA
- SBY
1 stop12h 00m
American Airlines
Tue 6/26:40 am
SBY
- SEA
1 stop19h 18m
American Airlines
Deal found 3/28![American Airlines logo]()
$686
This Delta deal was found by Cheapflights users on 3/27. 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.
Thu 9/179:50 pm
SEA
- PHL
Nonstop5h 15m
Delta
Sat 9/194:05 pm
PHL
- SEA
1 stop10h 58m
Delta
Deal found 3/27![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 3/26. 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.
Sat 4/2511:11 pm
SEA
- PHL
1 stop6h 44m
Delta
Fri 5/87:10 am
PHL
- SEA
Nonstop5h 50m
Delta
Deal found 3/26![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 3/29. 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.
Sun 5/311:15 pm
SEA
- PHL
1 stop9h 59m
Delta
Fri 5/87:10 am
PHL
- SEA
Nonstop5h 50m
Delta
Deal found 3/29![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 3/25. 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 6/311:59 pm
SEA
- PHL
1 stop7h 31m
Delta
Sun 6/77:00 am
PHL
- SEA
Nonstop5h 59m
Delta
Deal found 3/25![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 3/28. 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 5/299:20 pm
SEA
- PHL
Nonstop5h 17m
Delta
Mon 6/16:45 pm
PHL
- SEA
1 stop8h 25m
Delta
Deal found 3/28![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 3/29. 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 5/286:00 am
SEA
- PHL
1 stop9h 39m
Delta
Sat 6/67:10 am
PHL
- SEA
Nonstop5h 50m
Delta
Deal found 3/29![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 3/25. 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 8/119:50 pm
SEA
- PHL
Nonstop5h 15m
Delta
Fri 8/216:40 pm
PHL
- SEA
1 stop8h 21m
Delta
Deal found 3/25![Delta logo]()
$363
This American Airlines deal was found by Cheapflights users on 3/26. 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 5/711:55 pm
SEA
- SBY
2 stops10h 26m
American Airlines
Sat 5/166:38 am
SBY
- SEA
1 stop7h 56m
American Airlines
Deal found 3/26![American Airlines logo]()
$798
This American Airlines deal was found by Cheapflights users on 3/30. 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 9/2410:33 pm
SEA
- SBY
1 stop18h 08m
American Airlines
Mon 9/285:00 am
SBY
- SEA
1 stop13h 40m
American Airlines
Deal found 3/30![American Airlines logo]()
$920
This American Airlines deal was found by Cheapflights users on 3/26. 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 4/106:00 am
SEA
- SBY
1 stop8h 59m
American Airlines
Tue 4/146:38 am
SBY
- SEA
1 stop7h 56m
American Airlines
Deal found 3/26![American Airlines logo]()
$942
This American Airlines deal was found by Cheapflights users on 3/29. 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 4/1312:34 pm
SEA
- SBY
1 stop7h 20m
American Airlines
Fri 4/176:38 am
SBY
- SEA
1 stop7h 56m
American Airlines
Deal found 3/29![American Airlines logo]()
$1,398
Last-minute flights from Seattle to DelawareDiscover last-minute flight deals from Seattle to Delaware. Data last updated March 30, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Delaware. Data last updated March 30, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 3/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:12 pm
SEA
- PHL
2 stops26h 42m
Frontier
Mon 4/208:41 pm
PHL
- SEA
1 stop15h 46m
Frontier
Deal found 3/25![Frontier logo]()
$282
This Kiwi.com deal was found by Cheapflights users on 3/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/147:12 pm
SEA
- PHL
2 stops12h 41m
Frontier
Wed 4/158:41 pm
PHL
- SEA
1 stop15h 46m
Frontier
Deal found 3/25![Frontier logo]()
$292
This Kiwi.com deal was found by Cheapflights users on 3/28. 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 4/1610:57 am
SEA
- PHL
2 stops21h 43m
Frontier
Mon 4/208:41 pm
PHL
- SEA
1 stop15h 46m
Frontier
Deal found 3/28![Frontier logo]()
$281
This CheapOair deal was found by Cheapflights users on 3/27. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/164:20 pm
SEA
- PHL
1 stop10h 14m
Frontier
Sun 4/198:36 pm
PHL
- SEA
1 stop15h 51m
Frontier
Deal found 3/27![Frontier logo]()
$291
This Expedia deal was found by Cheapflights users on 3/30. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/174:20 pm
SEA
- PHL
1 stop10h 14m
Multiple Airlines
Mon 4/207:25 am
PHL
- SEA
Nonstop6h 05m
Multiple Airlines
Deal found 3/30![Multiple Airlines logo]()
$289
This Expedia deal was found by Cheapflights users on 3/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/187:12 pm
SEA
- PHL
1 stop7h 23m
Multiple Airlines
Wed 4/227:25 am
PHL
- SEA
Nonstop5h 58m
Multiple Airlines
Deal found 3/28![Multiple Airlines logo]()
$294
This Expedia deal was found by Cheapflights users on 3/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/199:54 pm
SEA
- PHL
1 stop29h 56m
Multiple Airlines
Wed 5/67:22 am
PHL
- SEA
Nonstop5h 58m
Multiple Airlines
Deal found 3/28![Multiple Airlines logo]()
$295
This Southwest deal was found by Cheapflights users on 3/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/249:00 pm
SEA
- PHL
2 stops10h 35m
Southwest
Tue 4/282:00 pm
PHL
- SEA
2 stops11h 30m
Southwest
Deal found 3/25![Southwest logo]()
$285
This Kiwi.com deal was found by Cheapflights users on 3/27. 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.
Fri 4/2410:11 pm
SEA
- PHL
2 stops28h 24m
Frontier
Fri 5/18:41 pm
PHL
- SEA
1 stop15h 46m
Frontier
Deal found 3/27![Frontier logo]()
$290
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/274:20 pm
SEA
- PHL
1 stop10h 14m
Frontier
Mon 5/45:01 am
PHL
- SEA
2 stops13h 04m
Frontier
Deal found 3/26![Frontier logo]()
$284
This Kiwi.com deal was found by Cheapflights users on 3/29. 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 4/2910:57 am
SEA
- PHL
2 stops15h 16m
Frontier
Sun 5/38:36 pm
PHL
- SEA
1 stop21h 29m
Frontier
Deal found 3/29![Frontier logo]()
$287
This Orbitz deal was found by Cheapflights users on 3/28. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/309:07 pm
SEA
- PHL
1 stop29h 06m
Frontier
Mon 5/48:41 pm
PHL
- SEA
1 stop16h 08m
Frontier
Deal found 3/28![Frontier logo]()
$286
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 March 30, 2026.
Search for one-way flight options from Seattle to Delaware. Find affordable one-way fares based on user searches. Data last updated March 30, 2026.
This Super.com deal was found by Cheapflights users on 3/30. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/412:42 pm
SEA
- PHL
1 stop13h 52m
Frontier
Deal found 3/30![Frontier logo]()
$139
This Kiwi.com deal was found by Cheapflights users on 3/30. 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.
Sat 4/257:12 pm
SEA
- PHL
2 stops33h 58m
Frontier
Deal found 3/30![Frontier logo]()
$140
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/111:07 am
SEA
- PHL
2 stops39h 28m
Frontier
Deal found 3/26![Frontier logo]()
$142
This CheapOair deal was found by Cheapflights users on 3/28. 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.
Wed 4/158:07 pm
SEA
- PHL
1 stop30h 27m
Frontier
Deal found 3/28![Frontier logo]()
$143
This Kiwi.com deal was found by Cheapflights users on 3/30. 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.
Fri 4/2410:11 pm
SEA
- PHL
2 stops28h 24m
Frontier
Deal found 3/30![Frontier logo]()
$144
This Frontier deal was found by Cheapflights users on 3/28. 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.
Sun 4/194:20 pm
SEA
- PHL
1 stop10h 14m
Frontier
Deal found 3/28![Frontier logo]()
$145
This Kiwi.com deal was found by Cheapflights users on 3/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/269:54 pm
SEA
- PHL
2 stops37h 08m
Frontier
Deal found 3/25![Frontier logo]()
$146
This Kiwi.com deal was found by Cheapflights users on 3/29. 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.
Fri 4/176:10 pm
SEA
- PHL
2 stops32h 25m
Frontier
Deal found 3/29![Frontier logo]()
$148
This Kiwi.com deal was found by Cheapflights users on 3/27. 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.
Thu 5/287:50 pm
SEA
- PHL
2 stops48h 28m
Frontier
Deal found 3/27![Frontier logo]()
$150
This Frontier deal was found by Cheapflights users on 3/27. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/167:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Deal found 3/27![Frontier logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 3/27. 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.
Sat 5/1611:37 am
SEA
- PHL
2 stops34h 08m
Frontier
Deal found 3/27![Frontier logo]()
$152
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 March 30, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $281 (CheapOair) |
One-way from | $139 (Super.com) |
Popular in | December |
Cheapest in | October |
Average price | $430 |
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 March 30, 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
Thu 6/4
9:20 pm-5:35 am
Nonstop5h 15m
Philadelphia
Sat 6/6
7:10 am-10:00 am
Nonstop5h 50m
$329
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Sat 5/9
9:44 pm-6:02 am
Nonstop5h 18m
Philadelphia
Wed 5/13
7:16 pm-10:28 pm
Nonstop6h 12m
$329
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 4/21
9:55 pm-6:05 am
Nonstop5h 10m
Philadelphia
Sat 4/25
7:22 am-10:20 am
Nonstop5h 58m
$337
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 9/18
7:35 pm-5:43 am
1 stop7h 08m
Philadelphia
Sun 9/20
7:05 am-10:04 am
Nonstop5h 59m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 9/17
9:50 pm-6:05 am
Nonstop5h 15m
Philadelphia
Sat 9/19
4:05 pm-12:03 am
1 stop10h 58m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Sat 4/25
11:11 pm-8:55 am
1 stop6h 44m
Philadelphia
Fri 5/8
7:10 am-10:00 am
Nonstop5h 50m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Sun 5/3
11:15 pm-12:14 pm
1 stop9h 59m
Philadelphia
Fri 5/8
7:10 am-10:00 am
Nonstop5h 50m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 6/3
11:59 pm-10:30 am
1 stop7h 31m
Philadelphia
Sun 6/7
7:00 am-9:59 am
Nonstop5h 59m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Fri 5/29
9:20 pm-5:37 am
Nonstop5h 17m
Philadelphia
Mon 6/1
6:45 pm-12:10 am
1 stop8h 25m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 5/28
6:00 am-6:39 pm
1 stop9h 39m
Philadelphia
Sat 6/6
7:10 am-10:00 am
Nonstop5h 50m
$339
Showing 1-10 of 28 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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