SoilHamony aims at developing transfer functions (TF) and pedotransfer functions (PTF) to support the implementation of the soil monitoring law (SML) and the EU Carbon Removal and Carbon Farming (CRCF) Regulation. It will also align with the EU mission: a soil deal for Europe, by supporting the development of a harmonized framework for soil monitoring in the EU towards healthy soils. TF will allow converting data obtained using national methods into those defined in the SML. The project will identify and collect existing source data, including archived samples, and existing derived and validated TF and PTF in a FAIR by design process. TF and PTF will be developed for main soil descriptors proposed in Annexe 1 and 2 of the SML. The effect of field sampling methods on the analytical results will also be characterized and recommendations to consider differences in methodologies will be provided. The TF will be validated with 4000 samples covering at least 21 MS and 80% of the EU land surface area with good representativeness of the various land uses. PTF will be validated without additional sampling but with new data to be collected from partners. The project will determine and operationalise the most reliable statistical methods for deriving TF and PTF. SoilHarmony will give access to the validated TF and PTF to all the entities responsible for the SML implementation and relevant stakeholders in an interoperable manner. A FAIR metadata catalogue and a soil database will efficiently gather already existing and newly acquired knowledge and data as DOI referenceable (meta)datasets. A converter toolbox will be freely available and composed of a back-end R package with built-in statistical methods and a user-friendly web application that will allow converting directly the national data into SML compliant data. MS will be actively involved in the construction through the 28 partners and their network, efficiently managed to maximise uptake of the results.