The objective of this study was to assess the socio-economical impacts of the payment for environmental services (PES) program in forest plantation in northern Costa Rica. The research methodology was based on a standard of principles, criteria and indicators (PC&I) in order to characterize the socioeconomic impacts of the program. The standard was the key factor for developing a semi-structured interview, with which the field information was collected. This information was afterwards analyzed quantitatively and statistically to identify the socio-economical impacts on each one of the beneficiaries. The study demonstrated that the PES program did not contribute to increase the economic welfare of the direct beneficiaries, questioning therefore the sustainability of the mechanism over time. Nevertheless, the study showed that the PES program improved the economic welfare of the indirect beneficiaries and related institutions, strengthening the relationships of the direct beneficiaries with financial institutions and forestry sector. Also, the program improved the perception of beneficiaries regarding the sustainable use of natural resources. In conclusion, the mechanism had positive impacts on indirect beneficiaries and related institutions, although it did not improve the socio-economic conditions of the direct beneficiaries, because the forest plantations had to compete with other activities such as agriculture and livestock.