Find the flight least likely to be delayed

1. Best overall#1 · Nonstop · 3h 11m

   6:00 AM → 11:11 AM

   90%

   arrive on time

   6:00 AM ONT → 11:11 AM IAH3h 11m

   United 1936

   Boeing 737-900 · 12–25 yrs old

   91% on time · 0.4% cancel
   Why this ranks here

   Find United 1936 fares ↗Opens this date on Aviasales

2. #2 · Nonstop · 3h 20m

   8:26 AM → 1:46 PM

   75%

   arrive on time

   8:26 AM ONT → 1:46 PM IAH3h 20m

   Frontier 3132

   Airbus A321 or A320neo · 2–10 yrs old

   76% on time · 0.7% cancel
   Why this ranks here

   Find Frontier 3132 fares ↗Opens this date on Aviasales

3. #3 · Nonstop · 3h 19m

   8:06 PM → 1:25 AM

   72%

   arrive on time

   8:06 PM ONT → 1:25 AM IAH3h 19m

   Frontier 2412

   Airbus A321 or A321neo · 2–11 yrs old

   72% on time · 0.5% cancel
   Why this ranks here

   Find Frontier 2412 fares ↗Opens this date on Aviasales

4. #4 · 1 connection · 5h 42m · separate tickets

   5:30 AM → 1:13 PM

   90%

   connections made

   83%

   arrive on time

   5:30 AM ONT → 6:35 AM LAS1h 05m

   Southwest 1695 · also flew as 2374

   Boeing 737 MAX 8 · 1–21 yrs old

   97% on time · 0.5% cancel

   Connect in LAS · 1h 30m · 92% chance to make it · separate tickets: collect and re-check bags, re-clear security; if you miss it the second airline does not have to rebook you

   8:05 AM LAS → 1:13 PM IAH3h 07m

   United 1181 · also flew as 1354

   Boeing 737 MAX 9 · 0–25 yrs old

   92% on time · 1.6% cancel
   Why this ranks here

   Flight 1: find Southwest 1695 (ONT–LAS) ↗Flight 2: find United 1181 (LAS–IAH) ↗Book each flight separately on Aviasales

5. #5 · 1 connection · 7h 13m · one ticket (United)

   6:00 AM → 3:13 PM

   95%

   connections made

   81%

   arrive on time

   6:00 AM ONT → 7:29 AM SFO1h 29m

   United 2363

   Boeing 737 MAX 9 · 0–8 yrs old

   91% on time · 0.9% cancel

   Connect in SFO · 1h 51m · 96% chance to make it · same ticket: the airline rebooks you if you miss it

   9:20 AM SFO → 3:13 PM IAH3h 53m

   United 1439

   Boeing 737 MAX 9 · 1–8 yrs old

   86% on time · 0.3% cancel
   Why this ranks here

   Find this United trip ↗Look for United 2363 + United 1439 on Aviasales

6. #6 · 1 connection · 6h 18m · one ticket (United)

   5:10 AM → 1:28 PM

   95%

   connections made

   78%

   arrive on time

   5:10 AM ONT → 8:32 AM DEN2h 22m

   United 2446

   Boeing 737-800 · 6–28 yrs old

   92% on time · 0.5% cancel

   Connect in DEN · 1h 18m · 95% chance to make it · same ticket: the airline rebooks you if you miss it

   9:50 AM DEN → 1:28 PM IAH2h 38m

   United 1915

   Airbus A321neo · 0–3 yrs old

   83% on time · 0.2% cancel
   Why this ranks here

   Find this United trip ↗Look for United 2446 + United 1915 on Aviasales

7. #7 · 1 connection · 7h 07m · one ticket (United)

   6:00 AM → 3:07 PM

   92%

   connections made

   81%

   arrive on time

   6:00 AM ONT → 7:29 AM SFO1h 29m

   United 2363

   Boeing 737 MAX 9 · 0–8 yrs old

   91% on time · 0.9% cancel

   Connect in SFO · 1h 26m · 93% chance to make it · same ticket: the airline rebooks you if you miss it

   8:55 AM SFO → 3:07 PM IAH4h 12m

   United 2110

   Boeing 737-900ER · 11–14 yrs old

   87% on time · 0.3% cancel
   Why this ranks here

   Find this United trip ↗Look for United 2363 + United 2110 on Aviasales

8. #8 · 1 connection · 7h 05m · one ticket (United)

   6:00 AM → 3:05 PM

   94%

   connections made

   79%

   arrive on time

   6:00 AM ONT → 7:29 AM SFO1h 29m

   United 2363

   Boeing 737 MAX 9 · 0–8 yrs old

   91% on time · 0.9% cancel

   Connect in SFO · 1h 41m · 95% chance to make it · same ticket: the airline rebooks you if you miss it

   9:10 AM SFO → 3:05 PM IAH3h 55m

   United 2498

   Boeing 787-9 or 757-300 · 0–24 yrs old

   84% on time · 0.3% cancel
   Why this ranks here

   Find this United trip ↗Look for United 2363 + United 2498 on Aviasales

9. #9 · 1 connection · 8h 21m · separate tickets

   7:00 AM → 5:21 PM

   99%

   connections made

   89%

   arrive on time

   7:00 AM ONT → 8:30 AM SMF1h 30m

   Southwest 3675

   Boeing 737 MAX 8 · 3–18 yrs old

   96% on time · 0.2% cancel

   Connect in SMF · 3h 05m · 99% chance to make it · separate tickets: collect and re-check bags, re-clear security; if you miss it the second airline does not have to rebook you

   11:35 AM SMF → 5:21 PM IAH3h 46m

   United 1949

   Boeing 737-800 or Airbus A320 · 10–28 yrs old

   90% on time · 0.1% cancel
   Why this ranks here

   Flight 1: find Southwest 3675 (ONT–SMF) ↗Flight 2: find United 1949 (SMF–IAH) ↗Book each flight separately on Aviasales

10. #10 · 1 connection · 9h 29m · one ticket (United)

    1:30 PM → 12:59 AM

    98%

    connections made

    86%

    arrive on time

    1:30 PM ONT → 2:59 PM SFO1h 29m

    United 1503

    Boeing 737 MAX 9 or Airbus A320 · 0–28 yrs old

    76% on time · 0.4% cancel

    Connect in SFO · 3h 55m · 99% chance to make it · same ticket: the airline rebooks you if you miss it

    6:54 PM SFO → 12:59 AM IAH4h 05m

    United 1702 · also flew as 2047

    Boeing 737 MAX 9 · 0–18 yrs old

    88% on time · 0.2% cancel
    Why this ranks here

    Find this United trip ↗Look for United 1503 + United 1702 on Aviasales

Aircraft and ages come from the planes each flight number actually flew in the last 3 months of data (FAA registry build years); airlines can swap planes.