  LISA Pathfinder satellite has been launched on 3th December 2015 toward the
Sun-Earth first Lagrangian point (L1) where the LISA Technology Package (LTP),
which is the main science payload, will be tested. With its cutting-edge
technology, the LTP will provide the ability to achieve unprecedented geodesic
motion residual acceleration measurements down to the order of $3 \times
10^{-14}\,\mathrm{m/s^2/{Hz^{1/2}}}$ within the $1-30\,\mathrm{mHz}$ frequency
band. The presence of the spacecraft itself is responsible of the local
gravitational field which will interact with the two proof test-masses.
Potentially, such a force interaction might prevent to achieve the targeted
free-fall level originating a significant source of noise. We balanced this
gravitational force with sub $\mathrm{nm/s^2}$ accuracy, guided by a protocol
based on measurements of the position and the mass of all parts that constitute
the satellite, via finite element calculation tool estimates. In the following,
we will introduce requirements, design and foreseen on-orbit testing
procedures.
