Two new strategies based on uncertainty estimation are proposed for antilock braking systems (ABSs). In one of the strategies, the uncertainties and the disturbances are estimated using inertial delay control (IDC), and the estimates are used in a backstepping-control-based braking system. In the other strategy, in addition to uncertainties, the states are also estimated using an inertial delay observer (IDO) for a sliding-mode-control (SMC)-based braking system. No knowledge of uncertainties, disturbances, and the road adhesion friction coefficient or their bounds is assumed. The stability of the overall system is proven, and the schemes are validated by simulation and experimentation in the laboratory.