Southwest Airlines has landed at the bottom of the punctuality table for North America's ten biggest carriers, with just 68.9% of its October flights arriving on time, according to Cirium's latest On-Time Performance Report. Nearly one in three completed Southwest flights ran at least 15 minutes late — a striking figure for an airline that built its reputation on no-frills reliability.
Delta Air Lines reclaimed the top spot with an 86.9% on-time rate, capping a steady recovery from a rough July, when only 75% of its flights were punctual. That figure climbed month by month through August and September, and also placed Delta third globally behind Hainan Airlines and Aeromexico. United came second in North America at 84.1%, with WestJet, JetBlue and Alaska rounding out the top five. American Airlines, despite operating the most flights of anyone on the list, managed only 80.1%.
Southwest's slide isn't happening in a vacuum. The airline has been rolling out the biggest changes in its history: checked-bag fees introduced in May, followed by assigned seating and a new boarding process in January. Since then, its on-time performance has averaged under 70% for six months, with year-on-year declines of up to nearly 12 percentage points. Charging for bags nudges passengers toward more carry-on luggage, which clogs overhead bins and slows boarding — and CEO Bob Jordan conceded on the October earnings call that on-time performance "is not where we want it to be."
The good news, if you're flying Southwest, is that the problem is delays rather than cancellations: the airline completed 99.5% of its scheduled flights. COO Andrew Watterson says turnarounds start well but lose minutes at the end of boarding, and two fixes kicked in during November — revised handling of gate-checked bags, and letting gate agents finalise flights on an iPad at the aircraft door. Bigger changes to crew reporting and scheduling follow in January.
The airport rankings tell a similar story. Six US airports made the global top 20 for on-time departures, and four of them are Delta hubs: Minneapolis-St. Paul (87%, eighth worldwide), Detroit, Salt Lake City and Atlanta — the latter handling over 67,000 flights in October, more than double any other airport in the top 20. Newark Liberty, which had a nightmare run last year, has quietly become one of the country's best performers. Notably, none of Southwest's major bases — Denver, Dallas Love Field, Chicago Midway, Baltimore — made the cut, and PlaneTrack data shows Southwest flights leaving Denver and Las Vegas on time only 63% of the time.
For travellers, the practical takeaway is straightforward: if punctuality matters — tight connections, a cruise departure, a wedding to attend — Delta via its hub cities is currently the safer bet in the US. Southwest still gets you there eventually, and cheap fares often compensate for the risk, but build a generous buffer into any same-day plans, especially through Denver or Las Vegas.
