FROM UAL.COM
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First in line: Priority check-in:
As a Premier member, you'll enjoy facilitated check-in at counters dedicated to Premier members. If Premier lines are unavailable, you can use United First® counters at most major terminals in the U.S. and Canada. On international flights, you are welcome to check in with United Business® customers.
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<font face="Verdana, Arial, Helvetica" size="2">This is the same for 1K
First in line: Priority check-in
As a Premier Executive member, you enjoy facilitated check-in at counters dedicated to Premier members. If Premier lines are unavailable, you can use United First® counters at most major terminals in the U.S. and Canada. On international flights, you are welcome to check in with United Business® customers.
You may also use Priority check-in counters when flying on any of our Star Alliance™ member carriers. Look for the "Star Alliance Gold" sign for your Priority check-in position.
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On the website it does not mention Star Silver.