Assess the potential epidemiological and economic impact of vaccinating the over-15 Colombian population against tetanus with a booster dose every 10 years.A cost-effectiveness analysis of tetanus vaccination with a booster dose every 10 years was conducted in Colombia and compared with the current strategy (2, 4, 6, 18, and 60 months). Estimates of the burden of disease were based on three official data sources. A Markov model from the perspective of the third party payer was developed. The time horizon was the lifetime of a person. Deterministic and probabilistic sensitivity analyses were conducted.In Colombia, 30 to 48 cases of tetanus resulting in 9.6 to 10.1 deaths are reported each year. Although booster vaccination for the entire population was cost-effective (the cost per disability-adjusted life year [DALY] avoided was US$ 11,314 in the entire population), gender-based differentiation of the results showed that it would not be cost-effective in women (cost per DALY avoided was US$ 4,903 in men and US$ 22,332 in women).This is the first study that evaluates the cost-effectiveness of a tetanus vaccine booster dose every 10 years in a developing country. Use of this measure would be cost-effective in Colombia, especially for men. As a result of the gender-based differences in the results, any decision about its use in women of childbearing age should take current vaccination into account.