Objectives Chronic Obstructive Pulmonary Disease (COPD) has a substantial impact on health care systems worldwide. Particularly, cardiovascular diseases such as ischemic heart disease (IHD) are frequent in individuals with COPD, but the economic consequences of combined COPD and IHD are by large unknown. Therefore, our study has the objective to investigate excess costs of IHD in COPD patients. Methods Out of German Statutory Health Insurance claims data we identified 26,318 COPD patients with and 10,287 COPD patients without IHD based on ICD-10 codes (COPD J44; IHD I2[0,1,2,5]) of the year 2011 and matched 9986 of them in a 1:1 ratio based on age and gender. Then, we investigated health care service expenditures in 2012 via Generalized Linear Models. Moreover, we evaluated a potential non-linear association between health care expenditures and age in a gender-stratified Generalized Additive Model. Results The prevalence of IHD in individuals with COPD increases with rising age up to a share of 50%. COPD patients with IHD cause adjusted mean annual per capita health care service expenditures of ca. €7400 compared with ca. €5800 in COPD patients without IHD. Moreover, excess costs of IHD have an inverse u-shape, peaking in the early (men) respectively late seventies (women). Conclusions IHD in COPD patients is associated with excess costs of ca. € 1,500, with the exact amount varying age- and gender-dependently. Subgroups with high excess costs indicate medical need that calls for efficient care strategies, considering COPD and IHD together particularly between 70 and 80 years of age.