One of the major challenges in nowadays particle physics and astrophysics is the determination of
the absolute neutrino mass scale. The HOLMES experiment aims at exploiting the calorimetric
approach to directly measure the neutrino mass through the kinematic measurement of the decay
products of 163 Ho electron capture (EC). The high energy portion of the calorimetric spectrum of
this decay is affected by the non-vanishing neutrino mass value. Given the small fraction of events
falling the region of interest, to achieve a high experimental sensitivity on the neutrino mass it
is important to have a high activity combined with a very small undetected pile-up contribution.
To achieve these targets, the final configuration of HOLMES foresees the deployment of a large
number of 163 Ho ion-implanted TESs characterized by an ambitiously high activity of 300 Hz
each. This contribution will provide an overview on the HOLMES project with its physics reach
and technical challenges together with the status of the major tasks that will bring HOLMES to
achieve a statistical sensitivity on the neutrino mass as low as 2 eV.