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Delta Air Lines / SAT → ATL

DL 1121 on time

Delta Air Lines 1121: San Antonio to Atlanta at 12:05 p.m.; Atlanta to San Antonio at 9:45 a.m. (past 12 months). Figures below the title are for SAT → ATL, its busiest leg

On time
76%
156 flights · likely 69–82%
Cancelled
1.9%
of scheduled flights
Typical arrival
−6 min
median vs schedule
When late
+97 min
average delay
Similar flights
81%
DL, same route & hour

About 1 in 4 DL 1121 flights from San Antonio arrived 15+ minutes late, diverted or cancelled over the past year (24%); 1.9% were cancelled. The typical flight landed 6 minutes early.

DL 1121: SAT → ATL

Scheduled to leave San Antonio at 12:05 p.m. local time. Over the past year it arrived on time 76% of the time (156 flights), worse than other DL flights on the route at that hour (81%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Apr 2025: too few flights (10 flights)AprMay 2025: 50% on time (26 flights)50MayJun 2025: too few flights (6 flights)JunMar 2026: 82% on time (17 flights)82MarApr 2026: 90% on time (20 flights)90AprMay 2026: 68% on time (31 flights)68MayJun 2026: 80% on time (30 flights)80JunJul 2026: 58% on time (31 flights)58JulAug 2026: 89% on time (27 flights)89Aug

By day of week

DayFlightsOn time
Monday2677%
Tuesday2580%
Wednesday2584%
Thursday2479%
Friday2378%
Saturday14—
Sunday19—

Why it was late

Airline (crew, maintenance, ops) 56%Late inbound plane 29%Air traffic & airport (NAS) 12%Severe weather 3%

All flights SAT → ATL · Connecting off DL 1121? Check the risk

DL 1121: ATL → SAT

Scheduled to leave Atlanta at 9:45 a.m. local time. Over the past year it arrived on time 83% of the time (156 flights), in line with other DL flights on the route at that hour (83%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Apr 2025: too few flights (10 flights)AprMay 2025: 69% on time (26 flights)69MayJun 2025: too few flights (6 flights)JunMar 2026: 88% on time (17 flights)88MarApr 2026: 90% on time (20 flights)90AprMay 2026: 77% on time (31 flights)77MayJun 2026: 87% on time (30 flights)87JunJul 2026: 68% on time (31 flights)68JulAug 2026: 93% on time (27 flights)93Aug

By day of week

DayFlightsOn time
Monday2681%
Tuesday2580%
Wednesday2592%
Thursday2483%
Friday2387%
Saturday14—
Sunday19—

Why it was late

Airline (crew, maintenance, ops) 60%Air traffic & airport (NAS) 28%Late inbound plane 12%

All flights ATL → SAT · Connecting off DL 1121? Check the risk

Questions

How often is DL 1121 from SAT to ATL late?

Delta Air Lines 1121 from San Antonio, TX to Atlanta, GA arrived 15 or more minutes late, was diverted or was cancelled on 24% of 156 scheduled flights between September 2025 and August 2026. 1.9% were cancelled.

How often is DL 1121 from ATL to SAT late?

Delta Air Lines 1121 from Atlanta, GA to San Antonio, TX arrived 15 or more minutes late, was diverted or was cancelled on 17% of 156 scheduled flights between September 2025 and August 2026. 1.3% were cancelled.

Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.