Route reliability

Washington (IAD) to Atlanta (ATL): which airline is most on time?

On-time arrivals, cancellations and long delays for every airline that reported nonstop flights from Washington, VA (IAD) to Atlanta, GA (ATL), September 2025 to August 2026.

Historical performance Official DOT data through August 2026 · Not live flight status

Washington, VAAtlanta, GA

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Three-letter airport codes, nonstop U.S. domestic flights. One direction at a time.

Route at a glance · September 2025 to August 2026

IAD to ATL

Washington, VA to Atlanta, GA

On time
75.9%vs 75.6% U.S. average About average
Cancelled
2.3%vs 1.9% U.S. average Worse than average
60+ min late
8.8%vs 8.1% U.S. average About average
Scheduled flights
4,003in 12 months4 airlines
Most reliable airline
United Airlines79.1% on time · 1,090 flights

On time about as often as the U.S. average, with more cancellations.

Compared with all U.S. flights, September 2025 to August 2026. “About average” means within 1.5 points for on time, 0.3 for cancelled and 1 for 60+ minutes late.

Airlines on this route

Ranked by on-time arrival

Airlines from IAD to ATL, September 2025 to August 2026. Rates are shares of all scheduled flights.
Airline On time Cancelled 60+ min late Avg delay when late Diverted Flights
1. United Airlines Most reliable 79.1% 0.7% 8.9% 78 min 0.3% 1,090
2. Delta Air Lines 77.3% 2.8% 7.8% 94 min 0.5% 2,233
3. Frontier Airlines 65.8% 3.2% 12.4% 78 min 0.2% 660
Republic Airways Operating carrier; sold as American Eagle, Delta Connection, United Express Insufficient sample (fewer than 50 flights) 20

On time = arrived within 15 minutes of schedule. Avg delay when late = average arrival delay of flights 15+ minutes late. "Most reliable" needs at least 300 flights in 12 months. Tap a heading to sort.

What this means

United Airlines has the strongest record on this route.

  • United Airlines had the best on-time record from Washington (IAD) to Atlanta (ATL): 79.1% of its 1,090 scheduled flights arrived within 15 minutes of schedule, compared with 65.8% for Frontier Airlines.
  • Republic Airways also flew this route but with fewer than 50 reported flights, too few to rate.
  • 2.3% of flights on this route were cancelled (about 1 in 43), about the same as the U.S. average of 1.9%.
  • 8.8% of flights, about 1 in 11, arrived an hour or more late. When a flight was late (15+ minutes), the average arrival delay was 86 min.
  • Overall, 75.9% of flights on this route arrived on time, about the same as the U.S. average of 75.6%.
  • Over the last 3 years, November was the most reliable month on this route (86.7% on time) and July the least reliable (63.1%).
  • Cancellations peaked in July, when 4.8% of flights were cancelled.
  • Flights scheduled to depart 8 am to 9 am were the most punctual (87.5% on time); flights scheduled to depart 5 pm to 6 pm were the least (67.2%).
  • In the other direction, Atlanta (ATL) to Washington (IAD), 74.7% of flights were on time and 2.1% were cancelled. Compare airlines ATL to IAD.

Best and worst months to fly IAD to ATL

Jan 75.4%
Feb 85.1%
Mar 80.6%
Apr 83.7%
May 72.5%
Jun 73.9%
Jul 63.1%
Aug 74.5%
Sep 85.3%
Oct 86.6%
Nov 86.7%
Dec 79.1%
Share of scheduled flights on time 12-month average 75.9%
All airlines combined, by calendar month, September 2023 to August 2026 (3 years pooled). Scale starts at zero.
Show as table
PeriodOn timeFlights
January 75.4% 775
February 85.1% 726
March 80.6% 829
April 83.7% 907
May 72.5% 1,033
June 73.9% 1,044
July 63.1% 1,013
August 74.5% 1,006
September 85.3% 930
October 86.6% 969
November 86.7% 889
December 79.1% 899
Best and worst calendar month by airline, September 2023 to August 2026.
AirlineBest monthWorst month
United Airlines November (89.1%) May (68.6%)
Delta Air Lines November (89.4%) July (62.1%)
Frontier Airlines October (80.4%) July (49.6%)

Month by month, last 12 months

Sep 87.9%
Oct 81.1%
Nov 76.7%
Dec 69.5%
Jan 77.2%
Feb 83.2%
Mar 77.0%
Apr 86.4%
May 74.3%
Jun 75.3%
Jul 58.7%
Aug 67.2%
Share of scheduled flights on time U.S. average 75.6%
All airlines combined, September 2025 to August 2026. Scale starts at zero.
Show as table
PeriodOn timeFlights
Sep 2025 87.9% 315
Oct 2025 81.1% 334
Nov 2025 76.7% 322
Dec 2025 69.5% 321
Jan 2026 77.2% 281
Feb 2026 83.2% 262
Mar 2026 77.0% 305
Apr 2026 86.4% 354
May 2026 74.3% 405
Jun 2026 75.3% 381
Jul 2026 58.7% 366
Aug 2026 67.2% 357

Best and worst departure times

<6a Insufficient sample
6a 80.9%
7a 71.6%
8a 87.5%
9a 84.4%
10a 80.8%
11a 87.2%
12p 80.0%
1p Insufficient sample
2p Insufficient sample
3p 75.1%
4p Insufficient sample
5p 67.2%
6p 64.6%
7p 68.4%
8p 45.5%
9p Insufficient sample
10p 74.6%
Share of scheduled flights on time
By scheduled local departure hour at IAD, September 2025 to August 2026. Hours with no scheduled flights are omitted. Scale starts at zero.
Show as table
PeriodOn timeFlights
Departing before 6 am Insufficient sample 30
Departing 6 am to 7 am 80.9% 503
Departing 7 am to 8 am 71.6% 313
Departing 8 am to 9 am 87.5% 409
Departing 9 am to 10 am 84.4% 64
Departing 10 am to 11 am 80.8% 323
Departing 11 am to noon 87.2% 78
Departing noon to 1 pm 80.0% 714
Departing 1 pm to 2 pm Insufficient sample 32
Departing 2 pm to 3 pm Insufficient sample 8
Departing 3 pm to 4 pm 75.1% 313
Departing 4 pm to 5 pm Insufficient sample 35
Departing 5 pm to 6 pm 67.2% 646
Departing 6 pm to 7 pm 64.6% 65
Departing 7 pm to 8 pm 68.4% 244
Departing 8 pm to 9 pm 45.5% 99
Departing 9 pm to 10 pm Insufficient sample 1
Departing 10 pm to 11 pm 74.6% 126
Woman at an airport window watching a plane take off
Photo: Depositphotos (licensed stock, illustrative only). Credits

Sources & data dates

Source
U.S. DOT Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (1987-present)
Period
September 2025 to August 2026 (12 months); month-of-year patterns September 2023 to August 2026
Data through
August 2026
Processed
2026-11-03
Scope
Nonstop scheduled flights from Washington, VA (IAD) to Atlanta, GA (ATL), one direction. Airlines that report to the DOT only.
Method
Rates use all scheduled flights as the denominator; cancelled and diverted flights count as not on time. Figures based on fewer than 50 scheduled flights are suppressed. Full methodology.

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