Update: Shortly after launching the ability for family pooling, United pull the option because of some tech issues. However, it seems they have fixed the issue and it's now on the site again.
While United doesn't have great award rates relative to its competitors, the ability to pool miles among friends and family (for free) could be quite useful. Neither American nor Delta have this feature, but Air Canada Aeroplan does.
Important Details
Joining And Leaving A Pool
Direct link to miles pooling page
Points Wire Note:
If there's one thing that disappoints me about this new feature, it's that you're restricted to booking flights operated by United. It would be much more useful if you could book award tickets on partner airlines.
For example, this restriction will prevent you from booking a United flight to Europe and connecting on a Star Alliance partner such as Austrian, Lufthansa, or Swiss. Since United doesn't fly to a ton of cities in Europe, that really restricts your options.
As for the restrictions on joining and leaving a pool, I think it's clear that you shouldn't join a pool unless you're about to book.
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