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DelayAtlas

Carrier route record

UASNAORD

United Airlines · Santa Ana to Chicago

Flights
1,040
Period
July 2025 to June 2026
Share of route
47%
Carriers
2
B+GRADE

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.

United on SNA to ORD lands a B+, about a point better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 1,040 flights, with a median arrival 4 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate United on SNA to ORD from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

Key figures

On time

79.0%

Arrivals under 15 minutes late, of 1,020 completed flights

Avg delay

62 min

Across delayed arrivals only, not all flights

Cancelled

0.58%

National rate is 1.81%

Whole route

76.7%

Every carrier on SNA to ORD, 2,212 flights

These figures cover 1,040 flights between July 2025 and June 2026. The median arrival is 4 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

Carrier by carrier

United against every carrier on SNA to ORD

United flew 1,040 of the 2,212 flights on SNA to ORD, about 47% of it. Its 79.0% on time is 2 points better than the route as a whole, which runs 76.7%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from United at 79.0% to American at 74.6%.

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

On-time performance by carrier on SNA to ORD
AirlineFlightsOn timeAvg delayCancelledGrade
United Airlines (this page)1,04079.0%62 min0.58%B+
American Airlines1,17274.6%85 min1.79%C

Departure window

When United runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

  • 5am–8am313 flights89.3%
  • 8am–11am263 flights83.3%
  • 11am–2pm169 flights74.7%
  • 2pm–5pm295 flights66.8%
  • 5pm–8pm
  • 8pm–5am

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 89.3% of the time, against 66.8% for the afternoon window. That is 23 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 313 flights scheduled in it.

Across the year

United on SNA to ORD through the year

On-time rate by calendar month78J83F69M77A82M76J74J86A82S82O73N87D
Darker means more delays. Figures are on-time percentages.December best, March worst

Delays peak in March, when the on-time rate falls to 68.7%. December is the strongest month at 86.5%. Moving a flexible trip across that boundary buys 18 points. January was the busiest month here, with 89 flights.

Across the week, Tuesday is the strongest day at 84.5% on time and Sunday the weakest at 64.4%. 20 points is a smaller lever than departure hour, but it is free.

On-time rate by day of the week78.6Mon84.5Tue80.5Wed76.0Thu81.9Fri82.5Sat64.4Sun
Monday: 78.6 percent on time. Tuesday: 84.5 percent on time. Wednesday: 80.5 percent on time. Thursday: 76.0 percent on time. Friday: 81.9 percent on time. Saturday: 82.5 percent on time. Sunday: 64.4 percent on time

Delay causes

Why United runs late on this route

One category carries most of the weight here. National Airspace System accounts for 66% of the 13,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

  • National Airspace System
    66%
  • Late-arriving aircraft
    20%
  • Carrier
    11%
  • Extreme weather
    4%

66% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 8,726 minutes out of 13,000, against a national NAS share of 21%. The split is drawn from 13,242 reported delay minutes.

Cancellations are rare at 0.58%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

Connections and stage length

What a delay here costs

5.7% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.

At 1,726 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

The return leg is a different operation and performs like one: it runs 75.2% on time across 1,040 flights, 4 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 4 points of difference.

One caution: this is a thin sample. 1,040 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking United on SNA to ORD

Put together: treat all of this as provisional. 1,040 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 79.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 1,020 completed flights over 12 months sit behind that.

Related

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.