Fast handoff support is a basic requirement for an Internet-based wireless mesh network (WMN), aiming to guarantee mobile users to be continuously connected to the Internet, regardless of their physical locations or moving trajectory. Due to the multi-hop transmission of network-layer handoff signaling packets, handoff performance in WMNs can be largely degraded by the increasing number of wireless hops as well as the channel access contentions between data and signaling packets in the mesh backbone. However, these issues are ignored in existing handoff solutions and multi-channel medium access control schemes. In this paper, we address the seamless handoff support from a different perspective and propose a gateway scheduling-based handoff scheme in single-radio multi-hop WMNs. Our proposed handoff scheme can realize single-hop handoff signaling packet transmissions and eliminate the channel contentions between data and signaling packets. Simulation results show that the total handoff delay is improved significantly using our proposed gateway scheduling-based handoff scheme under various scenarios, as compared to existing handoff solutions in multi-hop WMNs. In addition, due to the single-hop transmission of signaling packets, the signaling overhead in the wireless mesh backbone can be substantially reduced.