United Flight 1721 Deals & Information (2026/2027)

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United Flight 1721 Route Deals From $148

The cheapest prices found with in the last 7 days for return flights were $257 and $148 for one-way flights to Kona Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Mon, May 25 - Mon, Jun 1
SFO
San Francisco Intl.
KOA
Kona Intl.
$257 Roundtrip, found 3 days ago
$257
Roundtrip
found 3 days ago
Select United flight, departing Mon, May 25 from San Francisco Intl. to Kona Intl., returning Mon, Jun 1, priced at $257 found 3 days ago
Tue, Jun 2 - Tue, Jun 9
SFO
San Francisco Intl.
KOA
Kona Intl.
$274 Roundtrip, found 5 days ago
$274
Roundtrip
found 5 days ago
Select United flight, departing Tue, Jun 2 from San Francisco Intl. to Kona Intl., returning Tue, Jun 9, priced at $274 found 5 days ago
Mon, May 25 - Mon, Jun 1
SFO
San Francisco Intl.
KOA
Kona Intl.
$277 Roundtrip, found 3 days ago
$277
Roundtrip
found 3 days ago
Select United flight, departing Mon, May 25 from San Francisco Intl. to Kona Intl., returning Mon, Jun 1, priced at $277 found 3 days ago
Sun, May 31 - Thu, Jun 4
SFO
San Francisco Intl.
KOA
Kona Intl.
$287 Roundtrip, found 1 day ago
$287
Roundtrip
found 1 day ago
Select United flight, departing Sun, May 31 from San Francisco Intl. to Kona Intl., returning Thu, Jun 4, priced at $287 found 1 day ago
Tue, May 26 - Tue, Jun 2
SFO
San Francisco Intl.
KOA
Kona Intl.
$293 Roundtrip, found 4 days ago
$293
Roundtrip
found 4 days ago
Select United flight, departing Tue, May 26 from San Francisco Intl. to Kona Intl., returning Tue, Jun 2, priced at $293 found 4 days ago
Tue, Jun 2 - Tue, Jun 9
SFO
San Francisco Intl.
KOA
Kona Intl.
$295 Roundtrip, found 5 days ago
$295
Roundtrip
found 5 days ago
Select United flight, departing Tue, Jun 2 from San Francisco Intl. to Kona Intl., returning Tue, Jun 9, priced at $295 found 5 days ago
Sun, May 31 - Thu, Jun 4
SFO
San Francisco Intl.
KOA
Kona Intl.
$296 Roundtrip, found 1 day ago
$296
Roundtrip
found 1 day ago
Select United flight, departing Sun, May 31 from San Francisco Intl. to Kona Intl., returning Thu, Jun 4, priced at $296 found 1 day ago
Sun, May 31 - Thu, Jun 4
SFO
San Francisco Intl.
KOA
Kona Intl.
$298 Roundtrip, found 1 day ago
$298
Roundtrip
found 1 day ago
Select United flight, departing Sun, May 31 from San Francisco Intl. to Kona Intl., returning Thu, Jun 4, priced at $298 found 1 day ago
Tue, Jun 2 - Tue, Jun 9
SFO
San Francisco Intl.
KOA
Kona Intl.
$302 Roundtrip, found 5 days ago
$302
Roundtrip
found 5 days ago
Select United flight, departing Tue, Jun 2 from San Francisco Intl. to Kona Intl., returning Tue, Jun 9, priced at $302 found 5 days ago
Wed, Jun 3 - Tue, Jun 9
SFO
San Francisco Intl.
KOA
Kona Intl.
$302 Roundtrip, found 16 hours ago
$302
Roundtrip
found 16 hours ago
Select United flight, departing Wed, Jun 3 from San Francisco Intl. to Kona Intl., returning Tue, Jun 9, priced at $302 found 16 hours ago
Mon, Jun 1 - Sat, Jun 6
SFO
San Francisco Intl.
KOA
Kona Intl.
$306 Roundtrip, found 1 day ago
$306
Roundtrip
found 1 day ago
Select United flight, departing Mon, Jun 1 from San Francisco Intl. to Kona Intl., returning Sat, Jun 6, priced at $306 found 1 day ago

Frequently asked questions

What route does flight number UA1721 take?
UA1721 operates between San Francisco, CA Airport (SFO-San Francisco Intl.) and KOA and flies direct. This journey typically takes 5 hours and 28 minutes.
What terminal does UA1721 fly out of?
Flight number UA1721 runs between SFO and KOA, and travelers taking this flight commonly depart from Terminal 3.
What kind of plane is on flight number UA1721?
There's a strong chance you'll be on a Boeing 737-900 if you've reserved a seat on flight UA1721. This flight usually heads off from San Francisco Intl. Airport (SFO) and lands at Kona Intl. Airport (KOA).
If I am not able to travel due to COVID-19, can I change my flight to a later date?
For more info about changing your UA1721 flight with Travelocity, please visit our Customer Service Portal.