Abstract Atlantic multidecadal variability (AMV) exerts profound climatic influences on both local and remote regions. Recent studies show that AMV can significantly modulate the El Niño–Southern Oscillation (ENSO) and its teleconnections. However, few studies have examined AMV impacts on seasonal prediction skill. Combining observational data and ensemble hindcasts, this study investigates AMV impacts on the seasonal prediction skill of sea surface temperature anomalies (SSTA) in subtropical North Atlantic. Results indicate that the seasonal prediction skill of spring SSTA over the subtropical North Atlantic is significantly higher in AMV positive phase than in AMV negative phase. Similar contrasts are observed in SSTA persistence. Further analyses reveal that these AMV‐related differences are closely linked to variations in upper‐ocean heat content, which arise primarily from disparities in heat convergence associated with the Atlantic Meridional Overturning Circulation.