Some of the vital problems around the conventional CMOS technology are leakage-power consumption, physical-scalability limits, and short-channel effects. These deficiencies have led to many studies about nano-scale designs. Quantum dot cellular automata (QCA) is a potential answer in nanotechnology. Scholars have considered the four-dot squared cell as the main factor in the QCA. Also, a full-adder is a fundamental unit in every digital system. However, the importance of cell and area consumption limitation in circuit designing has been completely ignored in most of the related studies. Therefore, in this paper, we have offered a one-bit multi-layer full-adder cell. The practical accuracy of the proposed circuits has been assessed using QCADesigner. According to the obtained results and the design, the presented design has efficient cell usage against all the prior designs regarding cell counts and area occupation, leading to around 7% improvement in cell number than the common full-adder design. The simulation outcomes have also shown that the introduced design has excellent efficiency regarding cell and area aspects.