Recently the phase 3 BEACON trial showed that the combination of encorafenib, cetuximab, and binimetinib versus cetuximab and irinotecan/FOLFIRI improved overall survival in pre-treated patients with metastatic colorectal cancer (mCRC) with BRAF V600E mutation. However, whether the benefits of these therapies justify their high costs has not been estimated in the USA. The purpose of this study was to evaluate the cost-effectiveness of BEC (binimetinib, encorafenib, and cetuximab), EC (encorafenib and cetuximab), and CI/CF (cetuximab with irinotecan or FOLFIRI) in patients with BRAF V600E-mutated mCRC after first- and second-line therapy. A Markov model was constructed to determine the costs and effects of BEC, EC, and CI/CF on the basis of BEACON trial outcomes data. Health outcomes were measured in life years (LYs), quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs). Deterministic and probabilistic sensitivity analyses characterized parameters influencing cost-effectiveness. Subgroup analyses were conducted as well. The QALYs gained in BEC, EC, and CI/CF were 0.62, 0.54, and 0.40, respectively. BEC resulted in ICERs of $883,895.73/QALY and $1,646,846.14/QALY versus CI/CF and EC, respectively. Compared with CI/CF, the ICER was $435,449.88/QALY in EC. The most sensitive parameters in the comparison among the three arms were the utilities of progressive disease and progression-free survival. Probabilistic sensitivity analyses showed that the probability of BEC and EC being cost-effective was 0%. In subgroup analyses, the ICER remained above the willingness-to-pay threshold of $150,000 per QALY. BEC and EC were not cost-effective regimens for patients with pre-treated mCRC with BRAF V600E mutation.