Financial viability and political will ultimately determine if tidal range power schemes are developed. This research aims to demonstrate a robust system to make initial estimates of capital costs for tidal range schemes that can be compared between systems and options. A levelised cost of energy (LCOE) is used to compare a tidal range barrage (Morecambe Bay) and a coastal tidal lagoon (North Wales); the schemes are set in context with other common energy sources. The results show the Morecambe Bay barrage generates marginally more electricity than the North Wales coastal lagoon and has a shorter impoundment at lower cost. However, the economic arguments for both schemes are similar; both are viable as the LCOE shows. Despite being shown to be financially viable, the sources of funding may remain a problem. Financial returns and two potential public funding mechanisms are discussed. The approach using two simple models makes a strong case for more detailed analysis and, in the current environmental, economic, and social climate serious decisions must be taken. Highlights · Initial estimation of capital cost for tidal range case studies using 5-main components · Optimisation of generator rating, number of turbines and sluices · Levelised cost of energy (LCOE). · Revenue and funding mechanisms.