It's never too late to join a frequent flyer program!
Nope, you don't need to be a frequent flyer member in order to get credit for a flight, but you should at least join it after if you want those miles! Here's how to retroactively get frequent flyer for a flight you already took.
There are three things you should note before submitting for missing miles. Most airlines do not actually require travelers to be a member of the frequent flyer program during the flight to get credit (except for Alaska).
Generally, the flight also needs to have occurred within the last year, except in the case of Delta. Delta requires a missing mileage request within nine months.
There's also a timeline for submitting the request for the missing mileage. Below is a guideline of each airline's policy, since they also don't want to get hit up immediately after the flight.
Please check out the footnotes for more information.
| Airline | Member1 | Flight Date2 | Request Timeframe3 |
|---|---|---|---|
| Alaska | Yes | Within 6 months for:
Within 12 months for all other flights. |
|
| American | No, though flights more than 30 days before enrollment date are not eligible for mileage credit. | Within 12 months. |
|
| Delta | No | Within 9 months. |
|
| Frontier | No | Within 180 days. |
|
| Hawaiian | No | Within 120 days. |
|
| JetBlue | No | Within 12 months. |
|
| Southwest | No | Within 12 months. |
|
| United | No4 | Within 12 months. |
|
