Regular sea level observations have been performed in Stockholm since 1825, yielding the longest unbroken series of monthly mean sea levels in the world. Applying Fourier analysis to these data we have investigated the annual and semiannual sea level variations as well as the pole tide. Whereas the semiannual variation has a fairly constant amplitude of about 4 cm, the annual variation shows a secular increase in amplitude from 8 to 10 cm. This increase is statistically significant at the 99% level. It is suggested that this change might be connected to secular changes of the oceanographic conditions that have been observed to occur in the northeastern North Atlantic, especially a movement of the oceanic polar front. The pole tide also shows a secular change. The amplitude for the 14.3-month Chandler period was less than 2 cm (below the noise level) during the previous century. During our own century the amplitude is 3 cm, 6 times the equilibrium tide. This might indicate that a meteorological forcing component close to the Chandler period has changed and added variability to the sea level at this period. ¿ American Geophysical Union 1990