https://www.tripadvisor.com/ShowTopic-g45963-i10-k9187723-Lyft_Promo_Codes_Question-Las_Vegas_Nevada.html
Lyft Promo Codes Question - Las Vegas Forum - Tripadvisor
Jan 19, 2016 ... Unfortunately no two promotions can be combined. However, I do believe you can choose which promotion you wish to use on your next ride in the payments section ...