BACKGROUND Specifications for determining acceptable limits of water sorption (WS) and solubility for interim denture resilient liners are lacking. OBJECTIVE The purpose of this in vitro study was to evaluate the WS and solubility of interim resilient materials throughout their lifespans. METHODS Specimens (n=10) of 7 tissue conditioners, Coe-Comfort (CC), Softone (ST), Rite-Line (RL), Dura Conditioner (DC), Hydrocast (HC), Dentusoft (DS), and Visco-gel (VG) and 2 interim resilient liners, Trusoft (TS) and Coe-Soft (CS), were submitted to desorption until weight stabilization. Next, they were immersed in distilled water at 37°C for 3, 5, 7, or 14 days and then weighed, dried, and reweighed. Data (%) were analyzed using 2-way ANOVA and the Tukey honestly significant difference (HSD) test (α=.05). RESULTS VG demonstrated the highest WS (12.06 ±0.93%-16.62 ±0.87%) and solubility (20.30 ±4.26%-23.59 ±2.24%; P<.05) percentages. Low WS values were presented by CC (2.23 ±0.53%-2.99 ±0.49%; P<.05). The WS showed no significant changes for CC, CS, and TS over 14 days (P>.05). SL presented intermediate solubility values (4.09 ±1.60%-8.80 ±1.15%), and the other materials showed values lower than 3.35 ±0.70%. CC, DC, DS, HC, RL, TS, and CS showed no changes in solubility throughout the 14-day trial. CONCLUSIONS Over the lifespan of a tissue conditioner (7 days), CC, RL, DC, HC, DS, CS, and TS presented suitable in vitro performance. Among the tested materials, CC, CS, and TS were considered best suited for denture relining for up to 14 days.