Route profile
CHS→BOS
Flight reliability, delays and best times to fly from Charleston to Boston, 818 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 6% of comparable major US routes (4,598 compared)
Calculated from 3,676 flights. How this is calculated
CHS → BOS arrives on time 71.8% of the time; the return trip, BOS → CHS, arrives on time 76.2% of the time, a 4.4-point gap between the two directions of the same city pair.
CHS → BOS spends 25.6 minutes on the ground on an 818-mile trip: 16.5 minutes from pushback to wheels-up at CHS and 9.1 minutes from touchdown to gate at BOS.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
This route's worst arrivals run unusually far past its typical one, a bigger gap than 96% of 4,598 comparable routes.
A typical arrival is 5 min early, but the worst tenth run 78 minutes worse than that.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,598 in the comparison.
What sets this route apart
Where CHS to BOS differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
CHS to BOS struggles most at 1 PM: 64.0% of its flights scheduled then arrive on time, 13.6 points behind the 77.6% on routes of similar length at the same hour. Against all other routes the gap is 13.1 points.
Thursday is the day CHS to BOS slips furthest against routes of similar length, 67.2% on time where they average 76.6%, 9.4 points lower. Against all other routes the gap is 9.6 points.
In September, CHS to BOS runs 19.5 points below routes of similar length, 63.0% on time to 82.5%. Against all other routes the gap is 19.4 points.
Delta Air Lines’ flights on CHS to BOS arrive on time 71.7% of the time, 9.4 points below the 81.1% it manages on its routes of similar length. Against all other routes the gap is 9.8 points.
CHS to BOS against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 1 PM departures | 64.0% | routes of similar length | 77.6% | −13.6 pts | 405 here, 134,728 there |
| Weekday: Thursday | 67.2% | routes of similar length | 76.6% | −9.4 pts | 500 here, 338,406 there |
| Month: September | 63.0% | routes of similar length | 82.5% | −19.5 pts | 308 here, 180,585 there |
| Airline: Delta Air Lines | 71.7% | routes of similar length | 81.1% | −9.4 pts | 1,188 here, 288,032 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 818 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
Why CHS → BOS flights are cancelled
July 2023 – July 2026
CHS → BOS cancelled 76 of 3,676 scheduled flights — about 1 in every 48. The reason filed most often was extreme weather, 40.8% of the cancellations coded on this route — about 1 in every 119 scheduled flights.
Share of cancellations
Of 76 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
31 cancellations, 40.8% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
30 cancellations, 39.5% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
15 cancellations, 19.7% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
76 coded cancellations were recorded on CHS → BOS; the section appears from 50.
When it goes wrong
July 2023 – July 2026
73 min late
against a median of 5 min early
CHS → BOS has an average that understates its risk: a typical arrival is 5 min early, but the worst tenth are 78 minutes worse than that. If the trip has something unmissable at the end of it, the median is the wrong number to plan against.
Percentiles over 3,676 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at BOS after arriving from CHS.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 42% | Likely to miss |
| 45 min | 27% | High risk |
| 60 min | 21% | High risk |
| 90 min | 13% | Some risk |
| 120 min | 8.0% | Some risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 2.07% of the time and diverts 0.19% of the time, which a late arrival never shows up in.
Chance of missing is the share of 3,593 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 73 minutes late (90th-percentile gate arrival delay), over 3,676 operations.
Any other layover length: connection checker.
Best time to fly
CHS → BOS flights departing 5–9 AM arrived on time 89.6% of the time, against 67.8% for 12–3 PM departures, a gap of 21.8 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 91.6% on time from 157 flights
- 7 AM to 8 AM: too few flights to score
- 9 AM: 88.3% on time from 120 flights
- 10 AM: 81.0% on time from 198 flights
- 11 AM: 81.2% on time from 214 flights
- 12 PM: 75.0% on time from 341 flights
- 1 PM: 64.0% on time from 417 flights
- 2 PM: 65.6% on time from 348 flights
- 3 PM: 70.5% on time from 467 flights
- 4 PM: 68.2% on time from 597 flights
- 5 PM to 6 PM: too few flights to score
- 7 PM: 65.3% on time from 248 flights
- 8 PM: 67.9% on time from 296 flights
- 9 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why CHS → BOS runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
Share of the delay minutes US DOT attributed to each cause for CHS → BOS. Only delays of 15 minutes or more are attributed.
Late-arriving aircraft is the largest cause on CHS → BOS, at 37.9%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 89.6% of the time and 12–3 PM departures 67.8%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| JetBlue | 2,071 | 71.1% | 1.88% | -4 min | 13.1% |
| Delta Air Lines | 1,218 | 71.7% | 2.38% | -6 min | 13.6% |
| Spirit Airlines | 210 | 70.4% | 2.86% | 0 min | 11.3% |
JetBlue flew 59.2% of the 3,499 flights listed.
Carriers on this route performed within a couple of percentage points of each other.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| B668 JetBlue | 1:19 PM | 994 | 70.9% |
Weekly and seasonal patterns
By day of week
Saturday is historically the most reliable day and Sunday the least, a gap of 11.6 percentage points.
By month
- Jan: 81.9%
- Feb: 78.7%
- Mar: 79.1%
- Apr: 77.4%
- May: 71.2%
- Jun: 71.6%
- Jul: 60.3%
- Aug: 67.8%
- Sep: 63.0%
- Oct: 69.7%
- Nov: 79.1%
- Dec: 72.6%
July is historically the weakest month and January the strongest, a spread of 21.6 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: too few flights to score (99)
- August 2023: too few flights to score (96)
- September 2023: too few flights to score (97)
- October 2023: too few flights to score (99)
- November 2023: too few flights to score (74)
- December 2023: too few flights to score (79)
- January 2024: too few flights to score (62)
- February 2024: too few flights to score (73)
- March 2024: too few flights to score (93)
- April 2024: too few flights to score (110)
- May 2024: 71.3% from 150 flights
- June 2024: 75.0% from 136 flights
- July 2024: 64.3% from 121 flights
- August 2024: 64.0% from 132 flights
- September 2024: 82.4% from 120 flights
- October 2024: too few flights to score (96)
- November 2024: too few flights to score (75)
- December 2024: too few flights to score (91)
- January 2025: too few flights to score (74)
- February 2025: too few flights to score (78)
- March 2025: 76.5% from 121 flights
- April 2025: 74.3% from 152 flights
- May 2025: 62.4% from 120 flights
- June 2025: too few flights to score (94)
- July 2025: too few flights to score (93)
- August 2025: too few flights to score (94)
- September 2025: too few flights to score (97)
- October 2025: too few flights to score (99)
- November 2025: too few flights to score (93)
- December 2025: too few flights to score (99)
- January 2026: too few flights to score (69)
- February 2026: too few flights to score (57)
- March 2026: too few flights to score (88)
- April 2026: too few flights to score (113)
- May 2026: 79.2% from 125 flights
- June 2026: too few flights to score (104)
- July 2026: too few flights to score (103)
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 70.9% against 73.5% in the 12 months before — declining by 2.6 percentage points.
Data and methodology
Calculated by FlyerIntel from 3,676 CHS → BOS flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed