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Soil CO₂efflux (F_soil) is commonly considered equal to soil CO₂production (R_soil), and both terms are used interchangeably. However, a non-negligible fraction ofR_soilcan be consumed in the subsurface due to a host of disparate, yet simultaneous processes. The ratio between CO₂efflux/O₂influx, known as the apparent respiratory quotient (ARQ), enables new insights into CO₂losses fromR_soilnot previously captured byF_soil. We present the first study using continuous ARQ estimates to evaluate annual CO₂losses of carbon produced fromR_soil. We found that up to 1/3 ofR_soilwas emitted directly to the atmosphere, whereas 2/3 ofR_soilwas removed by subsurface processes. These subsurface losses are attributable to dissolution in water, biological activities and chemical reactions. Having better estimates ofR_soilis key to understanding the true influence of ecosystem production onR_soil, as well as the role of soil CO₂production in other connected processes within the critical zone.