$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 9/6. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ILG
Jul 9 — Jul 161
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
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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 June 9, 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 June 9, 2026.
This Alaska Airlines deal was found by Cheapflights users on 6/5. 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 7/910:02 pm
SEA
- PHL
Nonstop5h 11m
Alaska Airlines
Sun 7/127:33 am
PHL
- SEA
Nonstop5h 59m
Alaska Airlines
Deal found 6/5![Alaska Airlines logo]()
$329
This American Airlines deal was found by Cheapflights users on 6/5. 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 7/38:20 am
SEA
- PHL
Nonstop5h 22m
American Airlines
Sun 7/127:35 pm
PHL
- SEA
Nonstop6h 21m
American Airlines
Deal found 6/5![American Airlines logo]()
$330
This Kiwi.com deal was found by Cheapflights users on 6/4. 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 8/187:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Tue 8/2512:42 pm
PHL
- SEA
1 stop24h 06m
Frontier
Deal found 6/4![Frontier logo]()
$332
This Kiwi.com deal was found by Cheapflights users on 6/8. 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 8/257:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Wed 9/212:42 pm
PHL
- SEA
1 stop28h 22m
Frontier
Deal found 6/8![Frontier logo]()
$333
This Southwest deal was found by Cheapflights users on 6/7. 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 8/115:20 am
SEA
- PHL
1 stop9h 40m
Southwest
Mon 8/245:55 am
PHL
- SEA
1 stop11h 00m
Southwest
Deal found 6/7![Southwest logo]()
$334
This United Airlines deal was found by Cheapflights users on 6/7. 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.
Fri 8/2111:00 pm
SEA
- PHL
1 stop8h 07m
United Airlines
Mon 8/243:48 pm
PHL
- SEA
1 stop8h 27m
United Airlines
Deal found 6/7![United Airlines logo]()
$335
This Travelocity deal was found by Cheapflights users on 6/6. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/309:27 pm
SEA
- PHL
Nonstop5h 13m
Multiple Airlines
Sat 10/33:25 pm
PHL
- SEA
1 stop10h 13m
Multiple Airlines
Deal found 6/6![Multiple Airlines logo]()
$336
This CheapOair deal was found by Cheapflights users on 6/5. 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 11/129:25 pm
SEA
- PHL
Nonstop5h 08m
Alaska Airlines
Sun 11/154:25 pm
PHL
- SEA
1 stop9h 09m
Alaska Airlines
Deal found 6/5![Alaska Airlines logo]()
$338
This Delta deal was found by Cheapflights users on 6/4. 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 8/269:29 pm
SEA
- PHL
Nonstop5h 11m
Delta
Wed 9/27:00 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 6/4![Delta logo]()
$339
This Southwest deal was found by Cheapflights users on 6/8. 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.
Thu 8/611:05 pm
SEA
- PHL
1 stop10h 20m
Southwest
Mon 8/106:05 pm
PHL
- SEA
1 stop8h 25m
Southwest
Deal found 6/8![Southwest logo]()
$340
This Expedia deal was found by Cheapflights users on 6/5. 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.
Tue 7/2810:02 pm
SEA
- PHL
Nonstop5h 11m
Multiple Airlines
Tue 9/293:25 pm
PHL
- SEA
1 stop10h 13m
Multiple Airlines
Deal found 6/5![Multiple Airlines logo]()
$341
This United Airlines deal was found by Cheapflights users on 6/6. 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 8/2611:04 pm
SEA
- PHL
1 stop7h 39m
United Airlines
Tue 9/110:30 am
PHL
- SEA
2 stops10h 12m
United Airlines
Deal found 6/6![United Airlines logo]()
$342
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 June 9, 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 June 9, 2026.
This Delta deal was found by Cheapflights users on 6/7. 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 8/119:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Tue 8/187:05 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 6/7![Delta logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 6/6. 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 8/259:27 pm
SEA
- PHL
Nonstop5h 13m
Alaska Airlines
Wed 9/26:08 pm
PHL
- SEA
Nonstop5h 52m
Alaska Airlines
Deal found 6/6![Alaska Airlines logo]()
$334
This Southwest deal was found by Cheapflights users on 6/5. 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 11/116:15 am
SEA
- PHL
2 stops12h 05m
Southwest
Fri 11/135:00 am
PHL
- SEA
1 stop8h 40m
Southwest
Deal found 6/5![Southwest logo]()
$378
This Delta deal was found by Cheapflights users on 6/4. 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 10/229:50 pm
SEA
- PHL
Nonstop5h 13m
Delta
Sun 10/257:05 am
PHL
- SEA
Nonstop6h 19m
Delta
Deal found 6/4![Delta logo]()
$329
This Alaska Airlines deal was found by Cheapflights users on 6/5. 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 11/129:59 pm
SEA
- PHL
1 stop14h 26m
Alaska Airlines
Sun 11/154:25 pm
PHL
- SEA
1 stop9h 09m
Alaska Airlines
Deal found 6/5![Alaska Airlines logo]()
$349
This Delta deal was found by Cheapflights users on 6/8. 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 8/189:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Sun 8/237:00 pm
PHL
- SEA
1 stop7h 59m
Delta
Deal found 6/8![Delta logo]()
$339
This American Airlines deal was found by Cheapflights users on 6/8. 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 9/248:20 am
SEA
- SBY
1 stop11h 39m
American Airlines
Tue 9/296:41 am
SBY
- SEA
1 stop19h 16m
American Airlines
Deal found 6/8![American Airlines logo]()
$772
This Delta deal was found by Cheapflights users on 6/4. 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 10/156:00 am
SEA
- PHL
1 stop8h 15m
Delta
Sun 10/187:05 am
PHL
- SEA
Nonstop6h 19m
Delta
Deal found 6/4![Delta logo]()
$339
This Alaska Airlines deal was found by Cheapflights users on 6/8. 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 7/810:02 pm
SEA
- PHL
Nonstop5h 11m
Alaska Airlines
Thu 7/167:33 am
PHL
- SEA
Nonstop5h 59m
Alaska Airlines
Deal found 6/8![Alaska Airlines logo]()
$386
This Delta deal was found by Cheapflights users on 6/8. 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 8/129:30 pm
SEA
- PHL
Nonstop5h 20m
Delta
Tue 8/183:58 pm
PHL
- SEA
1 stop10h 59m
Delta
Deal found 6/8![Delta logo]()
$339
This Delta deal was found by Cheapflights users on 6/6. 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 7/165:59 pm
SEA
- PHL
1 stop9h 16m
Delta
Mon 7/206:57 pm
PHL
- SEA
1 stop8h 01m
Delta
Deal found 6/6![Delta logo]()
$359
This Delta deal was found by Cheapflights users on 6/4. 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 7/157:15 am
SEA
- PHL
1 stop7h 24m
Delta
Sun 7/197:05 am
PHL
- SEA
Nonstop5h 56m
Delta
Deal found 6/4![Delta logo]()
$373
This American Airlines deal was found by Cheapflights users on 6/7. 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 9/48:10 am
SEA
- SBY
1 stop11h 48m
American Airlines
Mon 9/76:41 am
SBY
- SEA
1 stop17h 17m
American Airlines
Deal found 6/7![American Airlines logo]()
$774
This American Airlines deal was found by Cheapflights users on 6/7. 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 8/218:10 am
SEA
- SBY
1 stop11h 48m
American Airlines
Mon 8/246:41 am
SBY
- SEA
2 stops11h 15m
American Airlines
Deal found 6/7![American Airlines logo]()
$1,116
This American Airlines deal was found by Cheapflights users on 6/8. 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 9/248:20 am
SEA
- SBY
1 stop11h 39m
American Airlines
Mon 9/286:41 am
SBY
- SEA
1 stop7h 59m
American Airlines
Deal found 6/8![American Airlines logo]()
$1,283
This American Airlines deal was found by Cheapflights users on 6/7. 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 6/266:20 am
SEA
- SBY
2 stops11h 10m
American Airlines
Mon 6/296:40 am
SBY
- SEA
2 stops11h 13m
American Airlines
Deal found 6/7![American Airlines logo]()
$1,303
This American Airlines deal was found by Cheapflights users on 6/7. 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 7/247:26 am
SEA
- SBY
2 stops11h 37m
American Airlines
Mon 7/276:41 am
SBY
- SEA
2 stops10h 46m
American Airlines
Deal found 6/7![American Airlines logo]()
$1,303
Last-minute flights from Seattle to DelawareDiscover last-minute flight deals from Seattle to Delaware. Data last updated June 9, 2026 and is based on user searches.
Discover last-minute flight deals from Seattle to Delaware. Data last updated June 9, 2026 and is based on user searches.
This American Airlines deal was found by Cheapflights users on 6/5. 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 7/38:20 am
SEA
- PHL
Nonstop5h 22m
American Airlines
Sun 7/127:35 pm
PHL
- SEA
Nonstop6h 21m
American Airlines
Deal found 6/5![American Airlines logo]()
$330
This Southwest deal was found by Cheapflights users on 6/7. 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 7/35:30 am
SEA
- PHL
1 stop9h 50m
Southwest
Sat 7/412:00 pm
PHL
- SEA
2 stops11h 10m
Southwest
Deal found 6/7![Southwest logo]()
$354
This Delta deal was found by Cheapflights users on 6/5. 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 7/49:25 am
SEA
- PHL
Nonstop5h 10m
Delta
Mon 7/136:55 pm
PHL
- SEA
1 stop8h 04m
Delta
Deal found 6/5![Delta logo]()
$345
This Alaska Airlines deal was found by Cheapflights users on 6/5. 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 7/910:02 pm
SEA
- PHL
Nonstop5h 11m
Alaska Airlines
Sun 7/127:33 am
PHL
- SEA
Nonstop5h 59m
Alaska Airlines
Deal found 6/5![Alaska Airlines logo]()
$329
This Delta deal was found by Cheapflights users on 6/8. 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 7/912:05 pm
SEA
- PHL
1 stop8h 51m
Delta
Mon 7/136:55 pm
PHL
- SEA
1 stop8h 04m
Delta
Deal found 6/8![Delta logo]()
$349
This Alaska Airlines deal was found by Cheapflights users on 6/6. 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.
Fri 7/1010:29 pm
SEA
- PHL
1 stop13h 54m
Alaska Airlines
Sun 7/127:33 am
PHL
- SEA
Nonstop5h 59m
Alaska Airlines
Deal found 6/6![Alaska Airlines logo]()
$339
This CheapOair deal was found by Cheapflights users on 6/8. 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.
Tue 7/1410:40 pm
SEA
- PHL
1 stop13h 43m
Alaska Airlines
Sat 7/187:33 am
PHL
- SEA
Nonstop5h 59m
Alaska Airlines
Deal found 6/8![Alaska Airlines logo]()
$344
This American Airlines deal was found by Cheapflights users on 6/8. 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.
Tue 7/1410:35 pm
SEA
- PHL
Nonstop5h 13m
American Airlines
Sat 7/187:35 pm
PHL
- SEA
Nonstop6h 21m
American Airlines
Deal found 6/8![American Airlines logo]()
$357
This CheapOair deal was found by Cheapflights users on 6/7. 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 7/1510:02 pm
SEA
- PHL
Nonstop5h 11m
Alaska Airlines
Sat 7/187:33 am
PHL
- SEA
Nonstop5h 59m
Alaska Airlines
Deal found 6/7![Alaska Airlines logo]()
$334
This American Airlines deal was found by Cheapflights users on 6/7. 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 7/248:20 am
SEA
- SBY
1 stop11h 38m
American Airlines
Mon 7/276:41 am
SBY
- SEA
1 stop17h 54m
American Airlines
Deal found 6/7![American Airlines logo]()
$818
This Expedia deal was found by Cheapflights users on 6/5. 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.
Tue 7/2810:02 pm
SEA
- PHL
Nonstop5h 11m
Multiple Airlines
Tue 9/293:25 pm
PHL
- SEA
1 stop10h 13m
Multiple Airlines
Deal found 6/5![Multiple Airlines logo]()
$341
This Kiwi.com deal was found by Cheapflights users on 6/4. 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 7/307:06 pm
SEA
- PHL
2 stops14h 16m
Frontier
Tue 8/411:06 am
PHL
- SEA
1 stop27h 02m
Frontier
Deal found 6/4![Frontier logo]()
$350
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 June 9, 2026.
Search for one-way flight options from Seattle to Delaware. Find affordable one-way fares based on user searches. Data last updated June 9, 2026.
This Delta deal was found by Cheapflights users on 6/4. 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 9/69:29 pm
SEA
- PHL
Nonstop5h 11m
Delta
Deal found 6/4![Delta logo]()
$165
This Kiwi.com deal was found by Cheapflights users on 6/4. 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 9/17:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Deal found 6/4![Frontier logo]()
$166
This United Airlines deal was found by Cheapflights users on 6/7. 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 7/91:30 pm
SEA
- PHL
1 stop8h 53m
United Airlines
Deal found 6/7![United Airlines logo]()
$168
This Delta deal was found by Cheapflights users on 6/5. 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 7/79:20 pm
SEA
- PHL
Nonstop5h 09m
Delta
Deal found 6/5![Delta logo]()
$170
This United Airlines deal was found by Cheapflights users on 6/6. 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.
Tue 9/111:03 am
SEA
- PHL
2 stops10h 56m
United Airlines
Deal found 6/6![United Airlines logo]()
$172
This Kiwi.com deal was found by Cheapflights users on 6/4. 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 9/27:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Deal found 6/4![Frontier logo]()
$177
This Southwest deal was found by Cheapflights users on 6/7. 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 7/110:45 pm
SEA
- PHL
1 stop11h 35m
Southwest
Deal found 6/7![Southwest logo]()
$180
This Super.com deal was found by Cheapflights users on 6/8. 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.
Tue 6/307:41 pm
SEA
- PHL
1 stop13h 06m
Frontier
Deal found 6/8![Frontier logo]()
$181
This Kiwi.com deal was found by Cheapflights users on 6/4. 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 9/53:19 pm
SEA
- PHL
2 stops18h 04m
Frontier
Deal found 6/4![Frontier logo]()
$182
This Kiwi.com deal was found by Cheapflights users on 6/4. 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 8/208:13 pm
SEA
- PHL
2 stops20h 04m
Frontier
Deal found 6/4![Frontier logo]()
$185
This Kiwi.com deal was found by Cheapflights users on 6/4. 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 7/88:13 pm
SEA
- SBY
2 stops44h 41m
Multiple Airlines
Deal found 6/4![Multiple Airlines logo]()
$259
This Kiwi.com deal was found by Cheapflights users on 6/7. 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 8/198:13 pm
SEA
- SBY
2 stops44h 41m
Multiple Airlines
Deal found 6/7![Multiple Airlines logo]()
$278
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 June 9, 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 | $472 |
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 June 9, 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
Tue 8/11
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Tue 8/18
7:05 am-10:01 am
Nonstop5h 56m
$329
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 10/22
9:50 pm-6:03 am
Nonstop5h 13m
Philadelphia
Sun 10/25
7:05 am-10:24 am
Nonstop6h 19m
$329
Quickest round-trip
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 8/25
9:27 pm-5:40 am
Nonstop5h 13m
Philadelphia
Wed 9/2
6:08 pm-9:00 pm
Nonstop5h 52m
$334
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Tue 8/18
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Sun 8/23
7:00 pm-11:59 pm
1 stop7h 59m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 10/15
6:00 am-5:15 pm
1 stop8h 15m
Philadelphia
Sun 10/18
7:05 am-10:24 am
Nonstop6h 19m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 8/12
9:30 pm-5:50 am
Nonstop5h 20m
Philadelphia
Tue 8/18
3:58 pm-11:57 pm
1 stop10h 59m
$339
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 11/12
9:59 pm-3:25 pm
1 stop14h 26m
Philadelphia
Sun 11/15
4:25 pm-10:34 pm
1 stop9h 09m
$349
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Thu 7/16
5:59 pm-6:15 am
1 stop9h 16m
Philadelphia
Mon 7/20
6:57 pm-11:58 pm
1 stop8h 01m
$359
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 7/15
7:15 am-5:39 pm
1 stop7h 24m
Philadelphia
Sun 7/19
7:05 am-10:01 am
Nonstop5h 56m
$373
SeattlePhiladelphia
SEA - PHL
SEAPHL
Seattle/Tacoma Intl
Wed 11/11
6:15 am-9:20 pm
2 stops12h 05m
Philadelphia
Fri 11/13
5:00 am-10:40 am
1 stop8h 40m
$378
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
No data available for this route at this time. Please check back soon.
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