OBJECTIVES:  To perform a cost-effectiveness analysis comparing bevacizumab versus cetuximab (mCRC) in combination with FOLFOX (oxaliplatin, leucovirin, fluorouracil bolus and florouracil IV) or FOLFIRI (irinotecan, leucovirin, fluorouracil bolus and florouracil IV) in patients with KRAS wild type metastatic colorectal cancer. METHODS:  A partitioned survival model was developed with three health states (progression free survival, progression, death) assuming weekly cycles, a 12-year horizon and two treatment arms: bevacizumab+FOLFOX/FOLFIRI or cetuximab+FOLFOX/FOLFIRI. Efficacy and safety data were based on CALGB 80405 trial. Health resource use was captured through expert’s opinion and unitary costs were obatined using Portuguese official sources. Only medical costs were included (related with drug aquisition and administration, health state, adverse events and KRAS mutation test the latter only applicable in cetuximab arm) and considering the perspective of the Portuguese NHS. A 5% yearly discount rate was applied in costs and health consequences. Costs were expressed in 2016 euros. RESULTS:  Consequences were similar between the two interventions (QALYs and overall survival). Over a 12-year period, the model predicted a cost of €84,268 for treating one patient with bevacizumab + FOLFOX/FOLFIRI versus €103.305 with cetuximab + FOLFOX/FOLFIRI, resulting in a cost-saving of €19.000 per patient to the NHS. Acquisition cost of bevacizumab is lower than cetuximab (-€15.449 €/patient) as well as adverse event costs (-€22), KRAS test cost (-€192) and supportive care while on progressive disease (-€4.458). Components with higher cost in bevacizumab arm are FOLFOX/FOLFIRI acquisition (+€63/patient), drug administration (+€67) and supportive care while on SLP (+€953). CONCLUSIONS:  The use of bevacizumab in treating KRAS wild type results mCRC resulted in substantial cost-savings to the Portuguese NHS, representing a cut of 39% on the expenses of the biologic drug over a 12-year horizon.