  We use holography to study codimension-2 surface defects in 5d SCFTs
engineered by $(p,q)$ 5-brane webs. The three-dimensional defects are realized
by D3-branes ending on the brane web. We identify the holographic
representation of the defects in Type IIB $AdS_6$ solutions as probe D3-branes,
and study conformal and non-conformal defects which, respectively, preserve one
half and one quarter of the supersymmetry. For a sample of 5d SCFTs, including
the $T_N$ theories, we provide explicit solutions for conformal and
non-conformal defects. For the conformal defects we obtain their contribution
to the free energy on $S^5$.
