Delta vs United: On-Time Performance Compared

Last 12 months · Aug 2025 – Jul 2026

Data through July 2026 · Last updated October 18, 2026

Delta was more punctual than United over the last 12 months: 81.5% of its flights arrived on time, against 79.3%.

United cancelled fewer flights (1.0% vs 1.7%), and late flights averaged 71 minutes late on Delta vs 71 on United.

On the 96 routes both airlines fly regularly, Delta had the better on-time record on 29 and United on 67.

Delta vs United: key numbers

Last 12 months, all flights each airline operated.

DeltaUnited

On-time arrivals81.5%79.3%

On-time departures81.9%81.4%

Cancelled1.7%1.0%

Diverted0.3%0.3%

On-time arrival % each month, last 24 months.

DeltaUnited

70%80%90%

Aug ’24Nov ’24Feb ’25May ’25Aug ’25Nov ’25Feb ’26May ’26

Share of each airline’s reported delay minutes by cause, last 12 months.

DeltaUnited

Airline (carrier)44.7%25.6%

Weather4.1%4.2%

Air traffic system (NAS)21.6%34.0%

Security0.1%0.0%

Late-arriving aircraft29.5%36.2%

96 routes where each airline had at least 100 completed flights in the last 12 months; the 25 busiest are shown. Better on-time rate in bold.

Route	Delta on time	United on time	Delta flights	United flights
LGA → ORD	68.9%	67.3%	2,306	4,665
ORD → LGA	70.6%	67.3%	2,306	4,665
SFO → LAX	72.1%	78.5%	2,374	3,297
LAX → SFO	62.9%	64.4%	2,374	3,291
ATL → EWR	71.6%	79.2%	3,045	1,994
EWR → ATL	80.0%	77.2%	3,045	1,994
ATL → ORD	69.2%	74.8%	2,630	1,668
ORD → ATL	80.5%	75.2%	2,628	1,668
IAH → LAX	87.8%	84.9%	646	3,439
LAX → IAH	84.9%	87.5%	646	3,438
DEN → LAX	81.2%	84.3%	746	3,077
LAX → DEN	80.3%	87.8%	744	3,079
ORD → MSP	67.6%	70.0%	1,421	2,378
MSP → ORD	68.4%	70.0%	1,422	2,375
IAH → ATL	80.1%	81.0%	2,520	1,263
ATL → IAH	75.6%	84.9%	2,521	1,261
ATL → DEN	79.4%	85.6%	2,810	941
DEN → ATL	86.0%	78.1%	2,810	941
IAH → LGA	77.4%	71.0%	1,345	2,381
LGA → IAH	75.0%	77.4%	1,345	2,381
ORD → BOS	69.3%	69.3%	970	2,735
BOS → ORD	65.8%	75.8%	970	2,733
LAX → ORD	72.4%	80.4%	151	3,388
ORD → LAX	75.5%	77.2%	151	3,387
ATL → IAD	78.2%	82.1%	2,224	1,094