Carrier route record

DLBWI→ATL

Delta Air Lines · Baltimore to Atlanta

Flights: 2,824
Period: July 2025 to June 2026
Share of route: 52%
Carriers: 4

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.

Delta on BWI to ATL earns an A. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 2,824 flights. The strongest carrier on the route with a full sample, Southwest Airlines, flew 1,573 at 77.4% on time.

Set against the rest of the country, Delta's BWI to ATL record is 9 points better than the US average of 77.6%. That gap is worth roughly 86 fewer late arrivals for every thousand flights.

On time

86.2%

Arrivals under 15 minutes late, of 2,760 completed flights

Avg delay

79 min

Across delayed arrivals only, not all flights

Cancelled

2.05%

National rate is 1.81%

Whole route

80.6%

Every carrier on BWI to ATL, 5,415 flights

These figures cover 2,824 flights between July 2025 and June 2026. The median arrival is 11 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

Carrier by carrier

Delta against every carrier on BWI to ATL

Delta flew 2,824 of the 5,415 flights on BWI to ATL, most of the route. Its 86.2% on time is 6 points better than the route as a whole, which runs 80.6%. Ranked by on-time rate it is first of four carriers on the route, where the range runs from Delta at 86.2% to Frontier at 68.0%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. Southwest Airlines arrives on time 77.4% of the time; Frontier Airlines manages 68.0%. Sample sizes sit next to every figure, because a two-point gap across 883 flights means less than a ten-point one.

On-time performance by carrier on BWI to ATL
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines (this page)	2,824	86.2%	79 min	2.05%	A
Spirit Airlinesthin sample	135	84.3%	67 min	0.74%	B+
Southwest Airlines	1,573	77.4%	60 min	1.34%	B
Frontier Airlines	883	68.0%	71 min	2.38%	C

Southwest leads Frontier by 9 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Flight by flight

Delta flight numbers on BWI to ATL

Departure window

When Delta runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 14 points, against 9 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am715 flights92.2%
8am–11am605 flights90.4%
11am–2pm456 flights87.0%
2pm–5pm519 flights81.3%
5pm–8pm505 flights78.5%
8pm–5am24 flights—

Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 92.2% of the time, against 78.5% for the evening window. That is 14 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 715 flights scheduled in it.

Across the year

Delta on BWI to ATL through the year

Darker means more delays. Figures are on-time percentages.September best, July worst

July is the worst month at 72.5% on time, 20 points below September, the best at 92.9%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. May was the busiest month here, with 255 flights.

Across the week, Wednesday is the strongest day at 90.0% on time and Sunday the weakest at 81.5%. 9 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Delta runs late on this route

Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 30,000 reported delay minutes.

Carrier
38%
Late-arriving aircraft
35%
National Airspace System
25%
Extreme weather
1%

35% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 30,000 reported delay minutes here, that single category outweighs weather by 26 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 30,212 reported delay minutes.

The largest share of delay minutes, 38%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 12,000 of the 30,000 delay minutes reported here.

Cancellations sit at 2.05% against a national 1.81%, which is ordinary. Diversions add another 0.21%.

Connections and stage length

What a delay here costs

5.3% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says 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 577 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 78.3% on time across 2,824 flights, 8 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 8 points of difference.

The sample behind these figures is 2,824 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.

What to do with this

Booking Delta on BWI to ATL

Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 92.9% on time and July 72.5%, a swing of 20 points. If the dates move at all, move them out of July before you think about anything else. 2,760 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures