The saying goes that if you can count, you can control. Addition is a fundamental operation for any digital system, digital signal processing or a control system. A fast and accurate operation of a digital system is greatly influenced by the performance of resident adders. In this regard, an efficient hybrid adder that combines a carry select adder and a ripple carry adder using QCA technology is designed to meet all the needs that is indispensable for a digital circuitry. QCA is an emerging nanotechnology, with the potential for higher speed, smaller size, and lower power consumption than transistor-based technology. Recent development in nano electronics provides a good introduction to the quantum mechanics of electrons, notions of free and confined electrons. Hence, with the help of QCA technology, the proposed hybrid adder produces a lesser area-delay product when compared to the previous adders and this proposed adder is also applied to a Wallace tree multiplier, here the area-delay product is reduced and speed of the multiplier is augmented.