The pan-boreal biome (> N45°) removes CO₂ from the atmosphere (i.e., it is a carbon sink). Fires can alter this carbon balance because they release CO₂ to the atmosphere but also initiate a long-term carbon sink during post-fire vegetation recovery. We found that historical fires of 1850–2009 have a small net sink contribution (~6 %) to the 2000–2009 regional carbon sink, which is a balance between immediate source effect of fires in 2000–2009 and sink effects of those in 1850–1999.