Route reliability record
IND→BOS
Indianapolis to Boston
- Flights
- 2,016
- Period
- July 2025 to June 2026
- Distance
- 818 mi
- Carriers
- 4
This route lands a B, level with the national rate of 77.6%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 2,016 IND to BOS flights, with a median arrival 10 minutes early.
Best time to fly IND to BOS: a 5am–8am departure, ideally on a Saturday. Flights in that window arrived on time 91.1% of the time and Saturday flights 87.9%, against 78.2% for the route overall.
The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
78.2%
Arrivals under 15 minutes late, of 1,964 completed flights
Avg delay
67 min
Across delayed arrivals only, not all flights
Cancelled
2.58%
National rate is 1.81%
Best carrier
Republic
78.2% on time across 1,961 flights
These figures cover 2,016 flights between July 2025 and June 2026. Beyond the headline rate, 9.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Which airline is most reliable on IND to BOS
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 |
|---|---|---|---|---|---|
| Delta Air Linesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| Allegiant Airthin sample | 18 | 83.3% | 76 min | 0.00% | B+ |
| Republic Airways | 1,961 | 78.2% | 67 min | 2.60% | B |
| Envoy Airthin sample | 36 | 71.4% | 60 min | 2.78% | C |
Flight by flight
Flights on IND to BOS
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 26 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am516 flights91.1%
- 8am–11am240 flights84.5%
- 11am–2pm463 flights80.4%
- 2pm–5pm201 flights66.8%
- 5pm–8pm537 flights65.3%
- 8pm–5am59 flights72.7%
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.1% of the time, against 65.3% for the evening window. That is 26 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 537 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 27 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
April is the best month on the calendar at 87.5% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. June was the busiest month here, with 177 flights.
Across the week, Saturday is the strongest day at 87.9% on time and Tuesday the weakest at 75.6%. 12 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. National Airspace System accounts for 51% of the 29,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 51%National Airspace System
- 27%Late-arriving aircraft
- 18%Carrier
- 4%Extreme weather
- 0%Security
51% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 15,000 minutes out of 29,000, against a national NAS share of 21%. The split is drawn from 28,867 reported delay minutes.
Cancellations run at 2.58%, against 1.81% nationally. That is about one flight in 40 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 actually costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.5% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 81.6% on time across 2,017 flights, 3 points above 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 3 points of difference.
The sample behind these figures is 2,016 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Work out the risk of missing a connection in BOS after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. April runs 87.5% on time and September 60.9%, a swing of 27 points. If the dates move at all, move them out of September before you think about anything else. 1,964 completed flights over 12 months sit behind that.
Common questions
IND to BOS questions
How often is IND to BOS delayed?
Roughly one flight in five arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 21.8% of the 2,016 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.
How reliable is IND to BOS compared with the rest of the country?
78.2% of flights arrive on time here against a national 77.6%, a difference of half a point in its favour. That is worth a B on this site's grading scale.
What time of day has the fewest delays on IND to BOS?
The 5am–8am departure window is the strongest at 91.1% on time. The 5pm–8pm window is the weakest at 65.3%, 26 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are September delays on IND to BOS?
September is the weakest month at 60.9% on time, compared with 87.5% in April. Across the year that is 27 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- BOS to IND — the return legseparate record
- Indianapolis International (IND) delay statistics
- Boston Logan International (BOS) delay statistics
- IND to ORD, a related route76.5%
- DCA to BOS, a related route71.4%
- IND to ATL, a related route88.5%
- Delta Air Lines on-time record100.0%
- Allegiant Air on-time record83.3%
- Republic Airways on-time record78.2%
- The US routes with the most cancellations
- The best time of day to fly, according to 7.04 million flight records
Direction matters. IND to BOS and BOS to IND are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed IND to BOS’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.