The superconducting and magnetic properties of HoNi2B2C single crystals are investigated through transport, magnetometry and small-angle neutron scattering (SANS) measurements. In the magnetic phases that enter below the superconducting critical temperature, the small-angle neutron scattering data uncover networks of magnetic surfaces. These likely originate from uncompensated moments, e.g., at domain walls pinned to crystallo-graphic grain boundaries. The field and temperature dependent behavior of SANS appears consistent with the metamagnetic transitions reported in earlier works.