Image courtesy United
Below are a variety of carriers with readily available mileage currencies that have options for Star Alliance Upgrades. Some are regional based and others are distance based. The booking classes, even when booking on the same airline (i.e. United) also vary at times.
ANA (Distance & Segment Based, i.e. 12k for 0-2000 Miles Economy to Business)
Avianca Star Alliance Partner Upgrade Charts & Rules
Singapore Airlines Star Alliance Partner Upgrade Charts & Rules
Turkish Airlines (best option, i.e. 10k domestic East Coast to Hawaii & available to be used even if the one booking isn't flying)
Fare Class Price Differences Can Be Substantial (over double in some cases)
United Airlines Mileage Upgrades
Elusive Partners May Not be Possible: Air Canada, Aer Lingus, Hawaiian
No Upgrades Available (Emirates)
More Tips:
Finding Saver Availability on United to Find Upgrade Availability
Finding Upgrade Availability on United
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