In the multicarrier transmissions such as orthogonal frequency division multiplexing (OFDM), one of the main problem is the high peak-to-average power ratio (PAPR) of transmission signals due to the superposition of many subcarriers. In this paper, we propose an approach for PAPR reduction using tone reservation (TR). The proposed approach guarantees a certain bound of PAPR reduction gain by using only one reserved subcarrier symbol. The bound depends on the ratio of the first and second peak magnitude. The proposed approach can be applied to not only one reserved subcarrier but also multiple reserved subcarriers. In the latter case, two methods are presented. To get more PAPR reduction gain, the proposed approach can be modified by adjusting the appropriate threshold.