Flight number record

DL 2109

Delta Air Lines · New York to Houston

Route: LGA → IAH
Departs: 18:29
Flights: 322
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2109, check with Delta Air Lines.

DL 2109 draws a D−. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is close to two hours behind schedule. Build slack into anything you connect to. That rests on 322 flights, with a median arrival 4 minutes early.

The national on-time rate over the same period is 77.6%, so DL 2109 runs 16 points behind the country as a whole. Across a thousand flights that is about 161 extra late arrivals.

On time

61.5%

Arrivals under 15 minutes late, of 309 completed flights

Avg delay

106 min

Across delayed arrivals only, not all flights

Cancelled

3.73%

National rate is 1.81%

1 hour+ late

23.3%

National rate is 8.1%

These figures cover 322 flights between July 2025 and June 2026. Beyond the headline rate, 23.3% 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.

Schedule

When DL 2109 flies

DL 2109 flies LGA to IAH without a single fixed slot. Its most common scheduled departure was 18:29, used on 97 of 322 flights, with 18:25 (35 flights) and 18:45 (35 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 18:2997 flights30.1%
Departs 18:2535 flights10.9%
Departs 18:4535 flights10.9%

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 18:29 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and DL 2109 runs 7 points worse at 61.5%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.

Against the route

DL 2109 next to LGA to IAH

Every carrier on LGA to IAH combined arrived on time 76.5% of the time across 4,060 flights, so DL 2109 is 15 points behind it. Delta flew 1,342 flights on the same city pair under all its flight numbers, including this one, and those ran 74.5% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 20 points.

DL 2109 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2109thin sample	322	61.5%	106 min	3.73%	D−
All Delta Air Lines on LGA–IAH	1,342	74.5%	85 min	3.73%	C−
All carriers on LGA–IAH	4,060	76.5%	85 min	2.59%	B
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 2109 quarter by quarter

DL 2109 did not run the same all year. Its best quarter was Jan–Mar 2026 at 75.0% on time and its weakest Oct–Dec 2025 at 40.8%, a swing of 34 points on roughly 81 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 202579 flights64.1%
Oct–Dec 202577 flights40.8%
Jan–Mar 202677 flights75.0%
Apr–Jun 202689 flights64.8%

Scale runs 30% to 80%. Rows with fewer than 30 flights show a dash.

By weekday, DL 2109 ranged from 57.1% on Sunday to 68.8% on Friday. With about 46 flights behind each day, a spread of 12 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why DL 2109 runs late

One category carries most of the weight here. Carrier accounts for 51% of the 13,000 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.

Carrier
51%
Late-arriving aircraft
25%
National Airspace System
23%
Extreme weather
1%

The largest share of delay minutes, 51%, 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 6,448 of the 13,000 delay minutes reported here. The split is drawn from 12,634 delay minutes reported on DL 2109.

Cancellations run at 3.73%, against 1.81% nationally. That is about one flight in 25 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 routes

What a delay on this flight costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 23.3% 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 1,416 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 same number turns up on three other city pairs in the data, including RSW to MSP (5), MSP to RSW (5) and BOS to CVG (1), but none flew often enough under DL 2109 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to LGA to IAH only.

One caution: this is a thin sample. 322 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 2109

For a booking, the cancellation rate is the figure to plan around on DL 2109: 3.73% of its 322 scheduled flights did not operate. A late arrival costs close to two hours, but a cancellation costs the day, so leave a later option open.

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