Thanks, just want to know if I can change my flight to an earlier one without the fee?

If your ticket is non refundable, change fee applies. Depending on whether it's your departing flight or return, you may have to requalify on a different fare as well. Unless you are on a bulk ticket like priceline, then you can check into standing by on the earlier flight that day without the fees.

Check availability and if it looks like the earlier flight won't sell out just show up early and go stand by for the early flight.

I'm not sure how to work it if you are checking a bag though?

I'm flyin US to ORD and will continue of from ORD via another carrier. Need luggage to show up with earlier flight if I go standby, and I'm not sure it will.

Even before 9-11, US was very particular about tagging luggage for standby, to ensure your luggage traveled with you.

I wouldn't expect any problems w/standby if you are willing to risk the seat being available.

When you check in for an earlier flight, if there are plenty of seats, the ticket counter may just confirm you on the flight rather than bothering with stand-by.

The notes on standing posted above are very tru and good. I would simply go that route!

As a note, UA allows same day changes gratis if the same route and fare code is available for PremExs. Only the fare code has to be available for same day changes for 1Ks.