OnTimeStats

Historical on-time performance

Chicago to Grand Rapids

137 miData through May 2026Source: US DOT · BTS

Flights on MDW–GRR arrive on time 75% of the time over the last 12 months.

On-time rate75%arrived within 15 min
p90 delay45 min1 in 10 flights is worse (tail risk)
Cancelled0.8%of scheduled flights

based on 928 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • Southwest Airlines
    On-time75%
    Medianon time
    p9045 min
    Cancel0.8%
    Flights928

Why flights run late

Delay causes

  • Airline32%
  • Weather4%
  • Air traffic (NAS)12%
  • Late aircraft52%
  • Security1%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline0%
  • Weather100%
  • Air traffic (NAS)0%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 7 cancellations with a reported cause (BTS reports causes from June 2003).

Over time

On-time trend

By season

On-time rate by month

When to fly

Best time to fly MDW → GRR

All airlines · rolling 36 months (2023-06 .. 2026-05).

Best time of day

On-time rates are fairly even by time of day on this route — ranging from 64% to 87% on time.

  • Middays87% on time · p90 20 min · 635 flights
  • Mornings87% on time · p90 15 min · 572 flights
  • Afternoons77% on time · p90 35 min · 459 flights
  • Evenings70% on time · p90 45 min · 245 flights
  • Overnights64% on time · p90 70 min · 921 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 71% to 82% on time.

  • Saturdays82% on time · p90 35 min · 318 flights
  • Wednesdays82% on time · p90 25 min · 415 flights
  • Tuesdays81% on time · p90 35 min · 415 flights
  • Fridays74% on time · p90 50 min · 418 flights
  • Thursdays73% on time · p90 45 min · 419 flights
  • Mondays73% on time · p90 50 min · 415 flights
  • Sundays71% on time · p90 45 min · 432 flights

Keep exploring

Related pages

Methodology

A flight is on time when it arrives within 15 minutes of schedule — the US DOT / BTS standard. Median and p90(the “1-in-10 bad day”) are read from the full arrival-delay distribution, never averaged across periods.

Figures cover a carrier’s own BTS-coded flights. Cells below ~200 flights are flagged as limited data. All numbers are pre-computed from public BTS On-Time Performance data.