Abstract Using a tropical Pacific pacemaker experiment, we demonstrate that the tropical eastern Pacific (TEP) decadal sea surface temperature (SST) variability influences the Atlantic Multidecadal Variability (AMV) through two pathways. The TEP induces a North Atlantic SST tripole response that peaks 1 year later, primarily via modulation of net surface heat flux. The subpolar SST anomalies associated with this tripole response subsequently influence the strength of North Atlantic deep water formation and the Atlantic Meridional Overturning Circulation, ultimately leading to a monopole SST response in the North Atlantic about one decade later. The tripole and monopole responses account for 40% and 59% of the TEP‐forced AMV signal, respectively. The TEP‐forced AMV explains approximately 30% of the variance in the internal AMV, thus substantially modulating the phase transitions and intensity of the historical AMV. This identified TEP forcing should be carefully considered to improve simulations and predictions of the AMV.