This work analyzes the potential effect of SLR on the sensitivity of the Ebro delta to storm surge induced inundation through areas sheltered from wave action. Results show that, under current conditions, flooding is restricted to very extreme conditions under the synergic action of astronomical tide and surges. When considering the effect of SLR, the magnitude of the flooding will significantly increase even under low SLR rates. This is critical for the deltaic vulnerability in the coming decades, since the inner shoreline along bays will not be able to respond to SLR to maintain its relative elevation with respect to the MSL.