Surface modification has been proposed as an attractive mitigation strategy for combating heat exchanger fouling in the food industry and other sectors. Antifouling coatings manipulate the interactions between the surface and fouling precursors or fouling deposit to either extend the induction period before appreciable fouling starts and/or reduce the rate of deposition. A successful surface treatment should extend the time between cleaning operations, thereby reducing the operating cost of the system. A modified exchanger will, however, incur additional capital costs for replacement and this needs to be compared to the anticipated savings during operation. This paper considers the economic attractiveness of replacing existing exchangers by units with modified surfaces in a retrofit. Three cases are considered, which are modelled using fouling rates taken from studies in the literature. Antifouling performance is expressed in terms of (i) extended induction period before fouling starts, and/or (ii) reduced fouling rate. The annualised total cost (operating + annualised capital spend) is mapped for different combinations of these parameters to establish the economically favourable region for a coating at different coating prices. This allows the value pricing margin to be identified, where the expected benefits have to be split between the cost of the coating and the benefit to the manufacturer and operator. The case studies are (a) DLC-related surface modification to reduce aqueous crystallisation fouling; (b) fluorocarbon-based coatings which offer antifouling performance but can reduce heat transfer, for crystallisation fouling; and (c) fluorocarbon-based coatings in a dairy pasteuriser application. A novel strategy, of replacing stainless steel with fluorocarbon coated carbon steel, is also considered for case (b).