Last week, Uber rolled out a pricing program in Chicago that allows riders to pay $20 or $40 upfront to get UberX or UberPool rides at a flat rate, which works out to UberX trips at $8 each and UberPool trips at $3 each. Since this is a test, supplies are limited. UberPool also is offering a $2.25 promotion for riders on the South and West sides, from 6 to 10 a.m. and from 4 to 8 p.m. UberPool had offered a "$3.12 for the 312" rate in Chicago this summer.