Cast-in-place piles are the most commonly foundation type used in Cordoba city, Argentina. Foundation of buildings usually consists in concrete piles embedded in collapsible loess with the pile tip in contact with a lower and stiffer stratum, typically sand or cemented silt. Piles in loess are frequently designed using safety factor criteria for both, short- and long-term behavior. Usually, there is no information about the reliability of piles since safety factors do not provide information on failure probability. A reliability analysis is implemented in this work to predict the behavior of piles in the Argentinean loess. Reliability-based technique is used to compute the failure probability of piles for long- and short-term performance. Pile capacity is computed by theoretical formulations using classical bearing capacity factors. The skin resistance is estimated by the α method. Results show that failure probability for a short-term analysis is smaller than for long-term analysis. Also, failure probability increases as safety factor decreases. Finally, in order to obtain a given failure probability the safety factor to be considered depends on the pile type.