This paper presents a 2 × VDD tolerant I/O buffer using 1 × VDD devices, with hot-carrier and gate-oxide reliability considerations. The novel circuit for mixed voltage I/O buffer is proposed to solve the hot-carrier and gate-oxide reliability issues. The proposed circuit is designed in 22nm FinFET technology. The design can be used in any CMOS technology for 2 × VDD tolerant I/O buffer to reduce hot-carrier effect.