Today: UA 1874 at 05:15 is the safest bet, 3% chance of being 15+ min late; evening flights run 10–17%.

Safest bet today UA 1874 IAH 05:15 → DEN 06:47 · 3% chance 15+ min late · usually 96% on time Riskiest F9 3227 IAH 10:24 → DEN 12:01 · 30% chance 15+ min late · usually 65% on time

Against a calm day 13% average chance a nonstop arrives 15+ min late; 11% for the same flights on a calm-weather day

Every nonstop today

12-month record →

Ranked by the chance of arriving 15+ minutes late, with each flight’s on-time record over Aug 2025 – Jul 2026 beside it. Times are local. Pick a flight for its forecast. Click a column to sort.


UA 1874 United Flight history →	IAH 05:15	DEN 06:47	3%	1%	0.1%	96%
UA 2415 United	IAH 06:16	DEN 07:46	5%	2%	0.2%	no record
UA 1686 United	IAH 08:24	DEN 09:54	8%	3%	0.2%	no record
UA 1450 United Flight history →	IAH 09:32	DEN 11:08	10%	3%	0.2%	85%
UA 685 United	IAH 20:32	DEN 22:34	10%	3%	0.6%	no record
UA 1575 United Flight history →	IAH 07:20	DEN 08:52	11%	3%	0.1%	77%
UA 2787 United	IAH 10:44	DEN 12:28	13%	3%	0.2%	no record
UA 2168 United Flight history →	IAH 12:33	DEN 14:17	13%	3%	0.2%	86%
UA 2767 United Flight history →	IAH 15:00	DEN 16:43	13%	3%	0.6%	75%
UA 1654 United Flight history →	IAH 18:19	DEN 20:14	14%	3%	0.6%	66%
OO 5197 SkyWest	IAH 07:11	DEN 08:51	15%	4%	0.4%	no record
UA 470 United Flight history →	IAH 16:28	DEN 17:58	17%	4%	0.6%	65%
F9 3229 Frontier Flight history →	IAH 06:30	DEN 08:14	17%	4%	0.5%	88%
F9 3227 Frontier Flight history →	IAH 10:24	DEN 12:01	30%	6%	0.4%	65%

How these are worked out. Each flight’s odds are our forecast for that day; flights of airlines we don’t forecast yet use their 12-month record and are marked. Makes the connection: the first flight’s 12-month lateness curve, scaled so its chance of arriving 15+ min late matches the day’s forecast, at the layover minus the 45-minute minimum (90 on separate tickets). Arrives on time: first flight not cancelled × connection made × second flight not cancelled × second flight within 15 minutes, each from the day’s forecast.

About this data: forecast odds from our model for Tue, Oct 6 (newest published update); 12-month records from US DOT on-time data, Aug 2025 – Jul 2026, all US airlines; regional flights count under the airline that sells them. JSON