Anaerobic digestion (AD) is considered an important brick of the circular economy allowing to treat and stabilize organic residues, produce renewable energy and promote the return to soil of organic matter and mineral nutrients. Digestate has been historically seen as a biogas by-product with a fertilizing value while representing a significant cost sector to AD plant operators. A paradigm shift is now necessary as other renewable energy sources with lowering production costs tend to disrupt an AD economic model greatly relying on subsidized biogas valorisation either via electricity or purification to biomethane. This chapter is focused on digestate post-treatments allowing to generate value-added products while closing and enhancing the loop between major agricultural inputs and outputs, the latter being indirectly present in digestates. Several options exist to generate mineral fertilizers, soil amendments, organo-mineral fertilizers, biostimulants, biocontrol products, energy and beyond from digestate. Consumer behaviour and regulatory framework evolution are necessary for increasing the demand and enabling a more sustainable agriculture based on biosourced upcycled materials. A major global milestone has been recently achieved as the EU has introduced a new fertilizer regulation (CE 2019/1009) that will tend to boost the commercialisation of digestate-based products within the world’s largest common market.