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Delta Air Lines / JFK → SJU

DL 1966 on time

Delta Air Lines 1966: New York to San Juan at 8:00 a.m.; San Juan to New York at 1:10 p.m. (past 12 months). Figures below the title are for JFK → SJU, its busiest leg

On time
77%
304 flights · likely 72–82%
Cancelled
3.6%
of scheduled flights
Typical arrival
−12 min
median vs schedule
When late
+55 min
average delay
Similar flights
79%
DL, same route & hour

About 1 in 4 DL 1966 flights from New York arrived 15+ minutes late, diverted or cancelled over the past year (23%); 3.6% were cancelled. The typical flight landed 12 minutes early.

DL 1966: JFK → SJU

Scheduled to leave New York at 8:00 a.m. local time. Over the past year it arrived on time 77% of the time (304 flights), in line with other DL flights on the route at that hour (79%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 90% on time (30 flights)90SepOct 2025: too few flights (11 flights)OctNov 2025: too few flights (8 flights)NovDec 2025: too few flights (12 flights)DecJan 2026: 65% on time (31 flights)65JanFeb 2026: 64% on time (28 flights)64FebMar 2026: 90% on time (31 flights)90MarApr 2026: 90% on time (30 flights)90AprMay 2026: 77% on time (31 flights)77MayJun 2026: 83% on time (30 flights)83JunJul 2026: 52% on time (31 flights)52JulAug 2026: 90% on time (31 flights)90Aug

By day of week

DayFlightsOn time
Monday4470%
Tuesday4374%
Wednesday4384%
Thursday4377%
Friday4388%
Saturday4480%
Sunday4468%

Why it was late

Airline (crew, maintenance, ops) 47%Air traffic & airport (NAS) 46%Late inbound plane 5%Severe weather 2%

All flights JFK → SJU · Connecting off DL 1966? Check the risk

DL 1966: SJU → JFK

Scheduled to leave San Juan at 1:10 p.m. local time. Over the past year it arrived on time 81% of the time (263 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%Aug 2025: 90% on time (31 flights)90AugSep 2025: too few flights (10 flights)SepOct 2025: too few flights (6 flights)OctNov 2025: too few flights (8 flights)NovJan 2026: 89% on time (27 flights)89JanFeb 2026: 71% on time (28 flights)71FebMar 2026: 84% on time (31 flights)84MarApr 2026: 90% on time (30 flights)90AprMay 2026: 77% on time (31 flights)77MayJun 2026: 90% on time (30 flights)90JunJul 2026: 71% on time (31 flights)71JulAug 2026: 77% on time (31 flights)77Aug

By day of week

DayFlightsOn time
Monday3982%
Tuesday3871%
Wednesday3884%
Thursday3792%
Friday3792%
Saturday3781%
Sunday3768%

Why it was late

Late inbound plane 71%Airline (crew, maintenance, ops) 17%Air traffic & airport (NAS) 12%

All flights SJU → JFK · Connecting off DL 1966? Check the risk

Questions

How often is DL 1966 from JFK to SJU late?

Delta Air Lines 1966 from New York, NY to San Juan, PR arrived 15 or more minutes late, was diverted or was cancelled on 23% of 304 scheduled flights between September 2025 and August 2026. 3.6% were cancelled.

How often is DL 1966 from SJU to JFK late?

Delta Air Lines 1966 from San Juan, PR to New York, NY arrived 15 or more minutes late, was diverted or was cancelled on 19% of 263 scheduled flights between September 2025 and August 2026. 2.3% 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.