In this paper, the methodology of seaworthiness and stability analysis of a pontoon for holiday house has described. A 3D model of the pontoon was modelled in the NAPA software to perform hydrostatic analysis. It is necessary to emphasize the fact that hydrostatic analysis has been made for several drafts and trims of pontoons. The hydrostatic analysis yielded data such as displacement, moulded volume, longitudinal centre of buoyancy, the transverse metacentric height, change of displacement, moment to change trim, and more. This part of the analysis also includes the loading scale from which we can see the deadweight at a given draft. Further, it is necessary to make weight study to get moulded displacement for pontoon for a holiday house. The pontoon also includes capacity tanks, so it is necessary to know the accurate dimensions of the tanks and their position for further analysis. It is necessary to know the exact geometry of the tanks because of the free surface effect. When calculating the stability of the pontoon, it is necessary to determine the minimum metacentric height and the maximum distance from the keel to the centre of gravity. Intact stability conditions must be met for GM limit curves and also for KG curves. Intact stability criteria of the pontoon were tested for four loading conditions: - Lightship - Pontoon with 10% stock without passengers - Pontoon with 100% stock with passengers - Pontoon with 50% stock with passengers It is important to emphasize that all tasks meet the stability criteria.