Skip to content
WanderNerd
Check a flight

Flight Reliability

UA 503 · United Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and UA 503 moved between routes during this period. Numbers below combine all of them, so treat them as background, not a verdict. For a cleaner answer, check the route you are actually flying.

Combined across all its routes

76%
Arrive within 15 minutes
14 min
Average arrival delay
0.5%
Cancelled
5 min early
Median arrival delay

Based on 632 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon73%(101 flights)
  • Tue77%(90 flights)
  • Wed79%(90 flights)
  • Thu78%(96 flights)
  • Fri75%(93 flights)
  • Sat71%(58 flights)
  • Sun75%(99 flights)
On-time by departure window
  • 6–9 AM—(5 flights)
  • 9 AM–12 PM88%(307 flights)
  • 12–3 PM67%(216 flights)
  • 3–6 PM56%(94 flights)
  • 6–9 PM—(5 flights)
On-time trend by month
81%
May

Jun 78% → May 81% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202578%60
July 202561%88
August 202580%74
September 202589%54
October 202582%56
November 202571%42
December 202557%46
January 202667%43
February 202679%34
March 202674%31
April 202690%52
May 202681%47
Departures on time
79%
Diverted
0.3%
Flights flown
627
Months covered
12

Keep nerding

Based on 632 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.