This data set is related to the article "Deciphering the redistribution of excess heat in the North Atlantic" in Communication Earth and Environment by Marie-José Messias and Herlé Mercier. It provides time series of ocean heat content (OHC) at 25°N in the Atlantic Ocean from 1850 to 2018 in four layers (0–700m, 700–2000m, 2000–4000m, 4000m–bottom) and associated errors. The contributions of 9 source regions (Arctic Ocean, Nordic Seas, Labrador and Irminger Seas, north-eastern subpolar gyre, Mediterranean Sea, subtropical and tropical North Atlantic, subtropical and tropical South Atlantic, Sub-Antarctic Ocean and Antarctic Ocean) to the surface-to-bottom OHC at 25°N from 1850 to 2018 are also provided.