Crop residues potential for the bioeconomy is often limited under the basis of avoiding prospective soil organic carbon depletion. However, when processed in the bioeconomy the biomass carbon can be partially recovered in a stabilized degradation-resistant state in the coproducts. This study interlinks the theoretical basis between the coproducts’ characteristics and behavior in soils and the use of soil models to predict the effect of replacing crop residues with bioeconomy coproducts. Stemming from a revision of over 600 datasets we defined conversion coefficients from biomass C to coproduct (Cc) and their inherent recalcitrance in soils (CR) for pyrolysis (Cc: 48%, CR: 95%) and gasification biochar (Cc: 20%, CR: 95%), hydrochar (Cc: 31%, CR: 83%), digestate (Cc: 36%, CR: 68%) and lignocellulosic bioethanol solid (Cc: 44%, CR: 42%) and liquid (Cc: 21%, CR: 46%) coproducts. Different approaches to incorporate stabilized organic matter in soil models were investigated as well as the data requirements of a variety of soil models to set the basis for model adaptation in a dynamic harvest – return of C to explore future scenarios involving the coproducts return as a strategy to increase the bioeconomy feedstock provision while ensuring the maintenance of SOC stocks.