FlyerTalk Forums Expert How-Tos and Guides
 

If you want to keep all your existing miles, and thus want some new miles to post quickly and reliably, here are some ways, from cheapest to most expensive:

1. Take a survey at opinionmilesclub.com - not sure how long this takes to post.
2. If you have a United credit card, downgrade it to the no fee version that gives 1 mile/$2 and use it every so often. Will help with aging as well which is good for your credit score.
3. Buy a $5 giftcard (to Amazon or a local store) using the MileagePlusX app - miles post within seconds of making payment.
4. Dining option still works (as of May 22, 2014). Posted to United in about 3 weeks after activity. I think it is one of the easiest options. No need to even take survey if you dont want extra survey points. I didn't do it.
5. Buy a gift card and trade it to United for miles. See http://www.flyertalk.com/forum/21020349-post702.html for an example that cost $15, and resulted in miles posting in under 24 hours. If you are not a U.S. resident, then buy an acceptable gift card on eBay and ask seller to email you the gift card number and pin. The gift card can be purchased with anyone's credit card (or cash) and applied to anyone's M+ number (name on credit card and M+ account need not match). It is not known if e-gift cards work. Physical gift cards known to work are:
   • Lowes (home hardware, not hotel)
   • Barnes and Noble
     2013 Update: - Ref, Ref
     - Online bought GCs (i.e. e GCs) are not working successfully - Failed: Walmart, Lowes, NewEgg
     - Store bought cards that worked recently as per some members: Target, B&N
6. Buy miles directly from United. http://www.ualmiles.com/PersonalMile...Personal+Miles. The minimum purchase is about $75.
7. Buy a ticket on united.com, and once it tickets, purchase award maximizer. Look for a flight with a short distance, such as COS/DEN to keep the award maximizer cost low. Miles will post in under 24 hours. Cancel ticket within 24 hours to get a full refund.
   2013 Update: Ref, Ref
   This seems to be the simplest way to do it for low cost, without much running around or waiting or donating miles.
   - Bought an IAH > Austin ticket for 69/79 $.
   - Went back in to change/ modify ticket reservation and then Award Acc was offered - 500 miles for 17$. Bought it.
   - Miles posted in few hours. Cancelled the ticket. Refund to Visa card pending.
   Note: Buy any low cost short distance ticket, go back in and buy award accelerator and then cancel in 24 hr after award miles post.

Using miles for travel or upgrades or UC subscription is a mileage activity that will also reset the expiration. However those worried about expiration tend not to be regular travelers, so some not travel mileage uses for resetting expiration date are

1. Magazine subscriptions
2. Charitable giving
3. Mileage Purchases -- generally a poor use of miles

If your miles have expired, there are a couple of ways to re-instate the lost miles

1. Reinstatement Miles for a fee -- if the expiration is as recent as 18 months ago, for roughly 0.2 to 0.3cpm
2. Find a recent (last 12 months typically) hotel stay or rental car credit that has not yet been posted. If the date was prior to expiration that should reinstate the expired miles.