I have been a CO One Pass member since the 80's (joined the program through Eastern Airlines). My account has now about 135K miles in it. In addition I also have acounts in NW, DL. These two have few to no miles in them. AA has enough for a free domestic (Only 25K left after using miles for various trips to Venezuela)

Since 1998, I have lived in cities with little to no service by CO but good coverage by NW. When I have flown NW in the last decade, I have given my CO number.

Now I am relocating to the Netherlands for three years (although I will maintain a US mail address).

Since most if not all of my flights in the coming years will be on NW and/or KLM I am wondering if I should finally say bye to my OnePass usage and start using my NW FF number exclusively on future flights instead. On my return to the US I will likely live in a city that currently has no CO service at all but with good NW service.

I'm not a frequent flyer as most of you on this board. While in Europe I will be taking at most 4 transatlantic segments each year ( two r/t). And maybe one from EU to Asia per year. Most trips will be within Europe (most likely on KLM).

I have been hesitant to say good bye to my CO Onepass; mostly for sentimental reasons (used it now for 20+ years, and the fact that I know my number by memory.

What do you experts think? Time to start placing miles on the NW account? Keep in mind that I have 130K on my OnePass account now, but I have none on the NW Worldperks account.

I will be going to Europe in a few weeks on a NW ticket (one segment from Detroit to AMS on a KLM plane).

Probably should decide before then. Thanks for your feedbacks and your help.

WP is perfect for KL and NW TATL credit, so I would switch to NW to credit these miles but keep the CO account open. Do you fly C or Y? CO gives 200% in C (including even R-class) for residents of Europe.

Generally I think it's better to be elite on the airline that you fly most, so that if there is a problem, you have better access and treatment with them...so you'd probably get NW Silver in a calender year and then get priorty toll-free access to the reservation agents. Also likely more bonus miles and EQMs with the NW WP program. Plus you can burn your CO miles on NW flights too...