Subclinical ketosis (SCK) in dairy cattle is a metabolic disease that occurs around the calving period and increases the risk on other diseases. SCK and other diseases result in, e.g., milk losses, reduced pregnancy rate, culling, and therefore have environmental and economic consequences. This study aimed to estimate the environmental and economic consequences of SCK and related diseases in dairy farming. A dynamic stochastic simulation model at cow level was developed and combined with a life cycle assessment and partial budget analysis. The model was divided into 4 parts. In part one, cows receive a parity (1–5+) and a potential milk production. Cows subsequently have a risk on getting retained placenta or milk fever (part 2), SCK (part 3), and metritis, displaced abomasum, clinical ketosis, lameness or mastitis (part 4). The risk on diseases depends on parity and previous diseases. The model was parameterized using literature. Inputs are the number of dairy cows, prevalence of diseases and culling rate, outputs are the change in global warming potential (GWP) and profit per case of SCK. Outputs were divided in direct (SCK) and indirect (other diseases due to SCK) consequences, that were estimated with the attributional risk of SCK. Cows with (a combination of) diseases had: a reduced daily milk yield, discarded milk if treated, an increased calving interval, and risk of culling. Monte Carlo simulation was performed to find the variation in the output. Preliminary results showed that the costs increased from €33.0 (±31.3) to €55.2 (±58.3) and GWP increased from 1.3 (±1.3) to 1.8 (±2.0) % CO₂-e/unit milk per parity based on milk losses per case of SCK. Results differ per parity (P < 0.001) due to differences in milk yield and risk on diseases. The highest contribution came from SCK (68%). Other diseases particularly had an effect on the variation of the output. Future calculations will be extended by including reproduction and culling, and by performing sensitivity analyses. In conclusion, SCK has an effect on the environmental and economic performance of dairy farming.