Farmers’ endorsement is crucial to conserve biodiversity in permanent grasslands, but the lack of visibility on their economic value is a major obstacle. We studied the production costs (i.e., the cost to produce one Mg of dry matter) and the replacement costs (i.e., the cost to replace grassland fodder with a mixture of wheat, soya and cereal straw) of 59 permanent and two sown grasslands from the Vosges Mountains (eastern France). We measured profitability as the difference between replacement costs and production costs. Our results highlighted a strong variability between grasslands, with lower production costs associated to grazing and higher production costs associated to low productivity. Permanent grasslands with low productivity were also associated to low profitability, but our calculation did not take into account their high conservation status which could deliver public subsidies. However, 75 % of the mainly cut permanent grasslands were more profitable than the cut sown grassland, and 75 % of the exclusively grazed grasslands were more profitable than the grazed sown grassland. Overall, permanent grasslands can be more profitable than sown grasslands while protecting biodiversity. We argue for the maintenance of agri-environment schemes that preserve grasslands of high ecological interest.