Wave-in-deck (WID) loads occur when waves evolve high enough to hit the deck structure of offshore platforms. WID events impose large step increases in wave loads, making them one of the largest threats to offshore structures. In particular, local WID loads arise when these loading events only involve a localised part of the offshore structure. Accurate predictions of local WID loads are critical to the Serviceability Limit State (SLS) design of the offshore structures. This research adopts a momentum-flux model to accurately and efficiently predict local WID loads. In contrast to many other methods, the load prediction in this research is achieved without any empirical calibration.