The working-zone encoding (WZE) method employing locality of memory reference was previously proposed to reduce address bus switching activity. This paper presents an encoding method that retains the advantage of WZE in switching activity reduction, but does not incur excessive path delay and area overhead. The proposed method is scalable for large bus width. Our encoder (decoder) has up to 58% (64%) delay reduction and 70% (62%) area reduction for a 32-bit multiplexed address bus. The switching activity is increased by 15% (18%) for the case without (with) a cache if the switching activity overhead is not counted. If the overhead is counted, the switching activity is reduced by 32% (17%) for the case without (with) a cache.