OBJECTIVES:  To assess the economic impact following the inclusion of an intravitreal implant of dexamethasone for the treatment of diabetic macular edema (DME). METHODS:  A budget impact model was designed to estimate healthcare costs for adult patients with DME during a 3-year period (2016-2018), from the Spanish National Health System (NHS) perspective. Currently approved therapies were considered (dexamethasone intravitreal implant, aflibercept and ranibizumab). The target population was defined with an epidemiological algorithm applying prevalence (6.41%) and incidence (0.82%) of DME in diabetic patients, estimated from published sources. From the annual eligible population (152,290 in 2016; 170,465 in 2017 and 188,524 in 2018); 20%, 30% and 40% were assumed to be treated with dexamethasone, respectively. Detailed resource consumption reflecting clinical practice was provided from local experts in retina and vitreous. Annual total costs included: drug acquisition (based on frequency of injections per first, second and third year of treatment, considering public ex-factory prices with mandatory deduction and no drug wastage), intravitreal administration, patient monitoring, management of ocular adverse events (cataracts, increased intraocular pressure, endophthalmitis, vitreous haemorrhage and retinal detachment) and cardiovascular adverse events. Unitary costs (€, 2016) were obtained from national databases and literature. No discount rate was applied. Sensitivity analyses were performed to assess the model robustness. RESULTS:  The inclusion of intravitreal dexamethasone implant would lead to annual cost savings of -53.35 (-4.2%), -16.36 (-1.8%) and -7.69 million euros (-0.9%), for years 2016-2018. Total costs were reduced mainly by the fewer annual injections required by dexamethasone. The average incremental costs were -350, -96 and -41 euros per patient-year. Sensitivity analyses showed that a higher percentage of use of dexamethasone would result in greater savings. CONCLUSIONS:  The inclusion of an intravitreal dexamethasone implant for the treatment of DME would lead to cost-savings for the Spanish NHS, mainly by reducing the administration costs.