This analysis measures the net benefit that a landowner could obtain from changing current dry-land cereal fields into Stone pine plantations in Portillo and Viana (Valladolid, Spain). We apply cost–benefit analysis techniques to estimate the present value of Stone pine afforestation net benefit by considering an infinite series of forestry rotations. We simulate three Stone pine silviculture models at each of the two sites. In addition, we estimate landowner extended net benefits from Stone pine afforestation when we consider a hypothetical payment for the carbon sequestration service. Results show that, when government subsidies are included, Stone pine afforestation only offers positive landowner net benefit in Portillo when both medium and high-stocking silviculture models are applied. Taking into account carbon prices up to €45tC−1 (€12.3tCO2−1), Stone pine afforestation gives landowner positive extended net benefits for the three silviculture models simulated at the Portillo and Viana sites.