For climate monitoring purposes an average sea level series for the United States, from which a representative curve and a single-value rate were derived, is presented. In addition, the use of dynamic height is introduced in order to take into account the greatly differing latitudes of the tide stations used in the study. The series was obtained by averaging common length uninterrupted sea level elevations reduced from the tide gage measurements of each station. The averging was by coastal area. The curve, with amplitudes of the averaged meteorological and oceanographic oscillations of periods of less than 51/3yr attenuated more than 90%, shows the relative apparent secular trend and its changes for the United States as a whole. During the 36-yr period, 1940--1975, sea level rose along the coast of the United States at the average rate of 1.5 dynamic mm/yr.