A new low-frequency standing equatorial wave mode is described. It is composed solely of long Kelvin and Rossby waves, whereas previously described low-frequency modes involved short, eastward propagating Rossby waves. It is argued that these short waves travel too slowly to allow such modes to set up. A simple closed form expression is given for the new basin mode; this is also a new form for the sum of a Kelvin wave and its eastern boundary reflection.