tailodds FORECAST
Connection · one ticket · schedule Jun 6 – Jul 31, 2026 · records Aug 2025 – Jul 2026

Boston → San Francisco via Chicago: arrives on time 26%

  1. 17:00 BOS → 19:00 ORD
    UA 2040 · United · 3h 00m · 55% on time, 2.5% cancelled
  2. 1h 04m layover in Chicago (ORD) · 45 min minimum on one ticket
  3. 20:04 ORD → 22:57 SFO
    UA 1495 · United · 4h 53m · 45% on time, 1.4% cancelled

Total trip 8h 57m, scheduled departure to arrival (San Francisco is 3 h behind Boston). Times are local. Both flew on 55 of the last 56 days.

Makes the connection60%The first flight arrived more than 19 minutes late on 40% of the days it flew: too late for the 45-minute minimum connection on a 1h 04m layover.
Arrives on time26%First flight not cancelled (2.5% are) × connection made (60%) × second flight not cancelled (1.4% are) and within 15 minutes (45%).
Total trip8h 57mBOS 17:00 to SFO 22:57, layover included

Tight connection: often missed. The first flight is late enough to miss it on more than 1 day in 4.

Not yet counted: the second flight also leaving late (which helps), gate-to-gate distance at the hub, and rebooking after a missed connection.