Best Time to Fly ATL to ONT
Atlanta to Ontario — month-by-month delay data from the Bureau of Transportation Statistics.
Best month
January
1% on time
Worst month
January
1% on time
ATL → ONT on-time performance by month
24
25
26
JanFebMarAprMayJunJulAugSepOctNovDec
Worse
Better
Monthly breakdown
| Month | On-time | Cancel rate | Flights |
|---|---|---|---|
| January | 1% | 0% | 263 |
| February | 1% | 0% | 228 |
| March | 1% | 0% | 265 |
| April | 1% | 0% | 313 |
| May | 1% | 0% | 367 |
| June | 1% | 0% | 363 |
| July | 1% | 0% | 376 |
| August | 1% | 0% | 288 |
| September | 1% | 0% | 239 |
| October | 1% | 0% | 247 |
| November | 1% | 0% | 233 |
| December | 1% | 0% | 256 |
Frequently asked
What is the best month to fly from ATL to ONT?
January has the highest on-time rate at 1% for flights from Atlanta to Ontario.
What is the worst month to fly ATL to ONT?
January has the lowest on-time rate at 1%, often due to winter weather.
How often are ATL to ONT flights delayed?
On average, 1% of flights from ATL to ONT arrive on time. That means about 99% experience some form of delay.
Source: Bureau of Transportation Statistics.