Stick-slip phenomena at a low-velocity range are investigated to study the effect of brake pad size on friction instability, focusing on the contact plateaus on the pad. The friction test is performed using commercial brake pads in three different sizes. The results show that smaller pads produce higher stick-slip amplitudes within narrower velocity ranges. Friction levels are influenced by the total contact plateau area, whereas the stick-slip amplitude was affected by the size of high-pressure plateaus. The pronounced stick-slip with small pads is attributed to the large high-pressure plateaus that increase the static friction further with stick time, indicating that a smaller brake assembly could lead to a high propensity of friction-induced noise and vibrations.