Abstract Designing a wave energy converter with the proper size has always been challenging since it is a trade-off between many factors including cost, practicality, and energy output. In this paper a practical design procedure for sizing of heaving point absorbers wave energy converters is presented. Size can be represented by the body volume. Budal power bounds are deployed to obtain the body volume and annual mean absorbed power of the wave energy converter. Budal power bounds are determined for each sea state. Aiming a specific power capture ratio, several sets of design sea states with related design volume and annual mean absorbed power are defined. With the design objective of maximizing the ratio of mean power to submerged volume, and considering suitable design constraints, the best size is obtained. The proposed procedure will be then deployed for a case study and the design will be compared with an existing similar point absorber. The results show that the mean absorbed power does not depend on the size but is a function of selected sea states. Furthermore, the comparison study reveals that the proposed design procedure yields reasonable power characteristics.