Flight number record

DL 973

Delta Air Lines · Boston to Atlanta

Route: BOS → ATL
Departs: 10:10
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 973, check with Delta Air Lines.

DL 973 earns a B. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 365 flights, with a median arrival 7 minutes early.

Set against the rest of the country, DL 973's record is 7 points better than the US average of 77.6%. That gap is worth roughly 69 fewer late arrivals for every thousand flights.

On time

84.5%

Arrivals under 15 minutes late, of 355 completed flights

Avg delay

55 min

Across delayed arrivals only, not all flights

Cancelled

2.47%

National rate is 1.81%

1 hour+ late

5.1%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 7 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.

Schedule

When DL 973 flies

DL 973 flies BOS to ATL without a single fixed slot. Its most common scheduled departure was 10:10, used on 91 of 365 flights, with 10:15 (48 flights) and 11:15 (46 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 10:1091 flights24.9%
Departs 10:1548 flights13.2%
Departs 11:1546 flights12.6%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 10:10 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and DL 973 runs level with that at 84.5%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

DL 973 next to BOS to ATL

Every carrier on BOS to ATL combined arrived on time 78.5% of the time across 4,931 flights, so DL 973 is 6 points ahead of it. Delta flew 3,662 flights on the same city pair under all its flight numbers, including this one, and those ran 82.1% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 3 points.

DL 973 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 973	365	84.5%	55 min	2.47%	B
All Delta Air Lines on BOS–ATL	3,662	82.1%	75 min	1.77%	B
All carriers on BOS–ATL	4,931	78.5%	69 min	1.99%	B
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 973 quarter by quarter

DL 973 did not run the same all year. Its best quarter was Jul–Sep 2025 at 90.2% on time and its weakest Jan–Mar 2026 at 78.3%, a swing of 12 points on roughly 91 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.

Jul–Sep 202592 flights90.2%
Oct–Dec 202592 flights84.6%
Jan–Mar 202690 flights78.3%
Apr–Jun 202691 flights84.3%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, DL 973 did best on Wednesday at 94.2% on time and worst on Sunday at 72.0%. Each day rests on about 52 flights, so a gap of 22 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 973 runs late

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 3,039 reported delay minutes.

Late-arriving aircraft
39%
Carrier
29%
National Airspace System
24%
Extreme weather
7%

39% 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 3,039 reported delay minutes here, that single category outweighs weather by 5 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 3,039 delay minutes reported on DL 973.

Cancellations sit at 2.47% against a national 1.81%, which is ordinary. Diversions add another 0.27%.

Connections and routes

What a delay on this flight costs

5.1% 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 about an hour, which a normal layover absorbs.

The 946 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.

Every one of the 365 flights under DL 973 in the data flew BOS to ATL. The number was not reused on any other city pair, which makes this a clean record of one route.

One caution: this is a thin sample. 365 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 DL 973

For a booking, read DL 973 as 84.5% on time with 2.47% cancelled over 365 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Where to go next

A flight number here means Delta Air Lines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.

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