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Measurements of the changes in phase path of F-region reflections at normal incidence at Kodaikanal (77° 28'E, 10° 14'N, dip 3°N) from February 1991 to February 1993 are used to determine the variation of the equatorial evening F-region vertical drifts (<i>V</i> <i><sub>z</sub></i>) with season, solar and magnetic activity. It is found that on average, at Kodaikanal, the post-sunset peak in <i>V<sub>z</sub></i>(<i>V<sub>zp</sub></i>) is higher in equinox and local winter months than in local summer. The day-to-day variability in <i>V<sub> zp</sub></i> is highest in summer and lowest in winter. This seasonal trend persists even on magnetically quiet days (<i>A<sub>p</sub> </i>leq14). <i>V<sub>zp</sub> </i>is found to increase with 10.7 cm solar flux in all three seasons but tends to saturate for large flux values (>230 units) during local summer and winter months. Magnetic activity [represented by <i>A<sub>p</sub> </i>as well as the time-weighted accumulations of <i>a<sub> p</sub></i> and <i>a<sub>p</sub></i> (τ)] does not seem to have any statistically significant effect on <i>V<sub>zp </sub></i>, except during equinoctial months of moderate solar activity, when <i>V<sub>zp</sub></i> decreases as magnetic activity increases.