Carrier route record
DLBOS→CHS
Delta Air Lines · Boston to Charleston
- Flights
- 370
- Period
- September 2025 to August 2026
- Share of route
- 32%
- Carriers
- 3
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on BOS to CHS lands a B−, about a point worse than the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That rests on 370 flights, with a median arrival 4 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate Delta on BOS to CHS from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
76.2%
Arrivals under 15 minutes late, of 357 completed flights
Avg delay
71 min
Across delayed arrivals only, not all flights
Cancelled
3.24%
National rate is 1.89%
Whole route
76.5%
Every carrier on BOS to CHS, 1,149 flights
These figures cover 370 flights between September 2025 and August 2026. Beyond the headline rate, 8.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
Delta against every carrier on BOS to CHS
Delta flew 370 of the 1,149 flights on BOS to CHS, about 32% of it. Its 76.2% on time is about level with the route as a whole at 76.5%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from Republic at 85.0% to JetBlue at 75.3%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airwaysthin sample | 109 | 85.0% | 54 min | 1.83% | A |
| Delta Air Lines (this page) | 370 | 76.2% | 71 min | 3.24% | B− |
| JetBlue Airways | 670 | 75.3% | 71 min | 2.54% | B |
Flight by flight
Delta flight numbers on BOS to CHS
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When Delta runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 370 flights.
There are not enough flights in each departure window to split Delta's BOS to CHS record by time of day without the percentages moving on noise. The headline rate of 76.2% is the reliable figure here.
Across the year
Delta on BOS to CHS through the year
- Jul–Sep 202538 flights78.9%
- Oct–Dec 202592 flights68.1%
- Jan–Mar 202677 flights73.2%
- Apr–Jun 2026101 flights87.0%
- Jul–Sep 202662 flights71.9%
Scale runs 60% to 90%.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 76.2% on time across 370 flights.
Delta on BOS to CHS did not run the same all year. Its best quarter was Apr–Jun 2026 at 87.0% on time and its weakest Oct–Dec 2025 at 68.1%, a swing of 19 points on roughly 74 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
Across the week, Tuesday is the strongest day at 83.7% on time and Sunday the weakest at 66.0%, a spread of 18 points.
Arrival by arrival
How late Delta on BOS to CHS runs when it is late
Delta on BOS to CHS often beats the schedule: 96 of 357 completed flights, 27%, arrived 15 minutes or more early. The 85 late arrivals split 30 under half an hour, 24 between 30 and 60 minutes, and 31 an hour or more.
- 15+ min early96 flights26.9%
- Within 15 min176 flights49.3%
- 15–29 min late30 flights8.4%
- 30–59 min late24 flights6.7%
- 1–2 hours late16 flights4.5%
- 2+ hours late15 flights4.2%
Scale runs 0% to 100%.
Share of 357 completed flights by arrival against schedule.
13 of 74 late departures made up the time and arrived on time, 18% of them. In the other direction, 24 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at CHS.
The worst days
Worst days for Delta on BOS to CHS
The latest arrival of the period was on 24 November 2025, 8 hours 32 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 24 November 2025 | 8 hours 32 minutes | Carrier |
| 20 March 2026 | 4 hours 38 minutes | Carrier |
| 25 April 2026 | 4 hours 24 minutes | Carrier |
| 19 December 2025 | 4 hours 13 minutes | Late-arriving aircraft |
| 15 December 2025 | 3 hours 47 minutes | Late-arriving aircraft |
Delay causes
Why Delta runs late on this route
Carrier accounts for 45% of the 6,057 delay minutes carriers reported here, and the remaining four split what is left.
- 45%Carrier
- 32%Late-arriving aircraft
- 22%National Airspace System
- 2%Extreme weather
The largest share of delay minutes, 45%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 2,715 of the 6,057 delay minutes reported here. The split is drawn from 6,057 reported delay minutes.
Cancellations run at 3.24%, against 1.89% nationally. That is about one flight in 30 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here costs
8.7% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
The 818 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.
The return leg is a different operation and performs like one: it runs 65.4% on time across 370 flights, 11 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 11 points of difference.
One caution: this is a thin sample. 370 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Delta on BOS to CHS
Put together: the delay figures matter less here than the 3.24% cancellation rate. A late arrival costs you a little over an hour; a cancelled flight costs you the day. Book the 11am–2pm departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 357 completed flights over 12 months sit behind that.
Related
Where to go next
- BOS to CHS, every carrier
- Delta on CHS to BOS, the return leg
- Republic Airways on BOS to CHS85.0%
- JetBlue Airways on BOS to CHS75.3%
- Delta Air Lines network-wide record
- Boston Logan International (BOS) delay statistics
- Charleston International (CHS) delay statistics
- The US routes with the most cancellations
- What a cancellation rate actually tells you (and what it hides)
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.