The method to calculate van der Waals interactions based on maximally localized Wannier functions (MLWFs), proposed by Silvestrelli [Phys. Rev. Lett. 100 (2008) 053002], has been implemented within the ab initio DFT program ABINIT. In addition to a brief review of the theoretical background behind this methodology, we present the details of the implementation, which will help users to assess van der Waals corrections in both molecular and periodic systems with a negligible additional computational cost. Some tests on argon dimer, argon FCC solid, benzene dimer and bilayer of graphene are presented. A discussion about the reliability of the method is also included.