Flight Check

Best Airline: BOS to SJU

Boston to San Juan — airline reliability comparison

Delta Air Lines is the most reliable airline on the BOS to SJU route with a 81% on-time rate, compared to Frontier Airlines at 48%. Based on 1,385 flights tracked.

This route involves weather-prone airports, which can affect reliability regardless of airline.

Source: Bureau of Transportation Statistics. Updated October 2026.

On-Time Rate by Airline

Delta Air Lines81%
JetBlue Airways68%
Spirit Airlines57%
Frontier Airlines48%

BOS to SJU Airline Comparison

AirlineOn-Time %Cancel %Avg DelayFlights
Delta Air LinesDLBest81%0.5%51m1,385
JetBlue AirwaysB668%1.5%73m4,387
Spirit AirlinesNK57%4.2%78m888
Frontier AirlinesF9Worst48%3.5%120m213

Route Overview

69%
Overall On-Time
74m
Avg Delay
1.7%
Cancel Rate
6,932
Total Flights
BOS to SJU Route DetailsReturn: SJU to BOS
BOS AirportSJU Airport

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Data last updated October 2026. Source: Bureau of Transportation Statistics.