69% of flights from Kansas City to Boston arrived on time over the past 12 months. That is worse than the typical U.S. route. The 9 a.m. departures ran on time 80% of the time; the 7 p.m. ones 70%. 16% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for MCI → BOS: when a flight was late, it was under 45 minutes late 40% of the time. About 1 in 7 flights landed an hour or more late, and 1 in 36 three hours or more; 2.9% were cancelled outright.
- On time or early69%
- 15–30 min late7.1%
- 30–60 min late7.5%
- 1–2 hours late6.9%
- 2–3 hours late3.7%
- 3+ hours late2.8%
- Diverted0.0%
- Cancelled2.9%
Share of all 650 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| Delta Air Lines | 590 | 72% | 3.2% | −10 min | 12.5% | +116 min | Delta Air Lines 62%, Republic Airways 38% |
| Southwest Airlines | 60 | — | — | — | — | — | Southwest Airlines |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at MCI). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | Delta Air Lines |
|---|---|
| 9 a.m. | 80% |
| 7 p.m. | 70% |
Last flight of the day
On MCI → BOS, each airline's last flight of the day was cancelled 2.7% of the time, against 2.2% for its earlier flights, about the same. It arrived 3+ hours late 3.6% of the time (earlier flights: 0.9%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| Delta Air Lines | 7:40 p.m. | 2.7% | 3.6% | 2.2% | first flight 9:40 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
By month
Each calendar month pooled over 2023–2026. Best: March (89%). Worst: July (69%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 103 | 66% | 3.9% |
| Tuesday | 96 | — | — |
| Wednesday | 94 | — | — |
| Thursday | 97 | — | — |
| Friday | 97 | — | — |
| Saturday | 63 | — | — |
| Sunday | 100 | 62% | 4.0% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: airline 12 · weather 4 · air traffic/airport 3
Month by month
Not enough months with data to draw a trend.
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Jun 28, 2026 | 3 | 0% | 0 |
| Jul 19, 2026 | 3 | 33% | 2 |
| Jul 7, 2026 | 3 | 33% | 0 |
| Jul 29, 2026 | 3 | 33% | 0 |
| Jun 7, 2026 | 3 | 33% | 0 |
Questions
How often are flights from MCI to BOS on time?
69% of 650 scheduled flights from Kansas City, MO to Boston, MA arrived within 15 minutes of schedule between September 2025 and August 2026. 2.9% were cancelled.
What is the best time of day to fly MCI to BOS?
Flights scheduled to leave at 9 a.m. were the most reliable (80% on time). The 7 p.m. departures were the least (70%).
What month has the most delays from MCI to BOS?
July (69% on time). The best month is March (89%), over 2023–2026.
Is the last flight of the day from MCI to BOS more likely to be cancelled?
Not much. Each airline's last MCI–BOS flight of the day was cancelled 2.7% of the time over the past year, against 2.2% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- BOS → MCI (return)
- Kansas City (MCI) delays by hour
- Flights into Boston Logan (BOS)
- Delta Air Lines on-time record
- Southwest Airlines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.