In this paper, we describe a bootstrapped nMOS switch that is modified to reduce leakage current for nMOS reversible energy recovery logic (nRERL) [1]. Conventional bootstrapped switches are not suitable for nRERL because they have nonadiabatic loss due to leakage current that flows while boosted. Therefore, we lowered the gate voltage of the isolation transistor in each bootstrapped switch to reduce this leakage current. With detailed analysis and simulation, we determined the range of the bias voltage, in which the switches can transfer full-swing input signals. We implemented a simple 8-bit nRERL microprocessor into silicon and measured its energy consumption to confirm our analysis. For the supply voltage of 1.8 V and the operating frequency of 880 kHz, we found that the microprocessor consumed about 8.5 pJ/cycle for 1.3 V < Vbias <1.6 V, which was just about a half of its energy consumption when Vbias = 1.7 V.