Easy question, from the CO website:
<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Elite Qualification Requirements
You may qualify for OnePass Elite membership based on the amount of paid flight/travel miles (actual or minimum, whichever is greater) or segments/points you earn in a calendar year on the following airlines and partners:
- Air Europa
- Alaska Airlines
- Azteca Airlines
- British European flybe.
- Cape Air
- Continental Airlines
- Continental Connection (Gulfstream International, Cape Air and CommutAir)
- Continental Micronesia
- Copa Airlines
- Delta Air Lines (only miles qualify)
- Delta Express (only miles qualify)
- Delta Shuttle (only miles qualify)
- Delta Connection (excluding AAEagle and Song; only miles qualify)
- ExpressJet Airlines (Continental Express flights)
- Hawaiian Airlines (interisland flights only)
- Horizon Air
- KLM Royal Dutch Airlines
- Northwest Airlines
- Northwest Airlink
- Alaska Airlines
- Select train routes
- Continental code-share flights operated by other airlines (Your ticket must indicate a Continental flight number in order for you to earn Elite miles.)
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