Flight number record

DL 2557

Delta Air Lines · Houston to Atlanta

Route: HOU → ATL
Departs: 06:00
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2557, check with Delta Air Lines.

DL 2557 earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 13 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 8 minutes early.

Set against the rest of the country, DL 2557's record is 13 points better than the US average of 77.6%. That gap is worth roughly 125 fewer late arrivals for every thousand flights.

On time

90.1%

Arrivals under 15 minutes late, of 355 completed flights

Avg delay

68 min

Across delayed arrivals only, not all flights

Cancelled

1.37%

National rate is 1.81%

1 hour+ late

3.4%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 8 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 2557 flies

DL 2557 flies HOU to ATL without a single fixed slot. Its most common scheduled departure was 06:00, used on 276 of 365 flights, with 05:45 (38 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 06:00276 flights75.6%
Departs 05:4538 flights10.4%

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 06:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 2557 runs level with that at 90.1%. 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 2557 next to HOU to ATL

Every carrier on HOU to ATL combined arrived on time 79.8% of the time across 2,917 flights, so DL 2557 is 10 points ahead of it. Delta flew 1,416 flights on the same city pair under all its flight numbers, including this one, and those ran 84.9% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 9 points.

DL 2557 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2557	365	90.1%	68 min	1.37%	A
All Delta Air Lines on HOU–ATL	1,416	84.9%	97 min	1.77%	B
All carriers on HOU–ATL	2,917	79.8%	66 min	1.13%	B
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 2557 quarter by quarter

Quarter by quarter DL 2557 held fairly steady: 94.6% in Jul–Sep 2025, 85.7% in Oct–Dec 2025, 89.0% in Jan–Mar 2026 and 91.1% in Apr–Jun 2026. A spread of 9 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights94.6%
Oct–Dec 202592 flights85.7%
Jan–Mar 202690 flights89.0%
Apr–Jun 202691 flights91.1%

Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, DL 2557 did best on Thursday at 96.2% on time and worst on Sunday at 83.7%. Each day rests on about 52 flights, so a gap of 13 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 2557 runs late

One category carries most of the weight here. Carrier accounts for 86% of the 2,365 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.

Carrier
86%
National Airspace System
10%
Extreme weather
4%

The largest share of delay minutes, 86%, 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 2,033 of the 2,365 delay minutes reported here. The split is drawn from 2,365 delay minutes reported on DL 2557.

Cancellations sit at 1.37% against a national 1.81%, which is ordinary. Diversions add another 1.37%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 3.4% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

The 696 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 2557 in the data flew HOU 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 2557

For a booking, DL 2557 has one of the better records a US domestic flight can show: 90.1% on time and 1.37% cancelled. That is a base rate, not a promise about any single 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