
United Flight AA399 Deals & Information (2025/2026)
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United Flight 399 Route Deals From $74
The cheapest prices found with in the last 7 days for return flights were $121 and $74 for one-way flights to Logan Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.
ORD
O'Hare Intl.
BOS
Logan Intl.
$121 Roundtrip, found 5 hours ago
$121
Roundtrip
found 5 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$139 Roundtrip, found 5 hours ago
$139
Roundtrip
found 5 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$142 Roundtrip, found 5 hours ago
$142
Roundtrip
found 5 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$142 Roundtrip, found 7 hours ago
$142
Roundtrip
found 7 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$144 Roundtrip, found 1 day ago
$144
Roundtrip
found 1 day ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$145 Roundtrip, found 2 hours ago
$145
Roundtrip
found 2 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$148 Roundtrip, found 1 day ago
$148
Roundtrip
found 1 day ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$149 Roundtrip, found 7 hours ago
$149
Roundtrip
found 7 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$150 Roundtrip, found 1 day ago
$150
Roundtrip
found 1 day ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$151 Roundtrip, found 7 hours ago
$151
Roundtrip
found 7 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$153 Roundtrip, found 16 hours ago
$153
Roundtrip
found 16 hours ago
ORD
O'Hare Intl.
BOS
Logan Intl.
$155 Roundtrip, found 4 hours ago
$155
Roundtrip
found 4 hours ago