We have some friends who live in Germany and just flew to the US, across, and back. I don't want them to "waste" any miles. Their trans-atlantic flights were on *A and I'll get them UA MP accts.

Their us dom flights were on DL & CO. I'm mostly familiar with the NW WP program. So my question is, which program is optimal for them.


They fly little. They will never get elite. They don't want the miles to expire. It'll take years to accumulate miles. Goal would be coach flights.

They could use my us address or their german one.

So NW, DL, or CO?

Thanks!