In the past, I've spoken of this benefit briefly, but as my move to Delta begins, there is another advantage to Delta that will help boost my mileage accounts in a few different ways. Crossover rewards is a program with Starwood hotel brands in agreement with Delta, Emirates, and Uber... though Uber may not technically be under the crossover program, it works the same from my point of view.
Crossover rewards are points and miles that are earned while flying Delta, or staying at a Starwood hotel. Since I am a huge fan and big user of Starwood, this is especially lucrative. The way the program works is that for any Starwood member, you will earn 1 point for every dollar spent on Delta flights. In other words, you will gain miles while flying Delta and gaining Starwood points. Starwood points can then be transferred to Delta, or any number of airline partners.
If you are a Delta elite customer, then you get rewards in the reverse direction as well. For every dollar you spend on a Starwood property, you get 1 mile added to your Delta account. So my normal behavior of staying at Starwood properties will earn me more usable miles on Delta.
While this won't be a huge source of points for me on the Delta side, it will likely be fairly significant on the Starwood side of the equation. Since those miles are transferable and carry bonus miles as well, it is a big deal and another added bonus to the switch to Delta.
The move I dive into this change, the more confident I am with the move. Being able to shift your loyalty is a powerful tool as Delta may someday be make things worse again and force another change, keeping flexible is always to your advantage.