We investigate how local magnetic correlations evolve when the classical pyrochlore spin ice ${\mathrm{Ho}}_2{\mathrm{Ti}}_2{\mathrm{O}}_7$ is transformed into the partially disordered stuffed compound ${\mathrm{Ho}}_2{\mathrm{TiO}}_5$. Neutron scattering measurements were analyzed using real space magnetic pair distribution function, reciprocal space reverse Monte Carlo, and half-polarized neutron powder diffraction methods to connect the average crystal structure with local magnetic correlations. Both compounds retain long-range $Fd\overline{3}m$ symmetry, but in ${\mathrm{Ho}}_2{\mathrm{TiO}}_5$ the average structure does not fully capture the local Ho–O, Ti–O, and O–O bond-length disorder associated with partial Ho/Ti occupancy. Despite this disorder, half-polarized neutron powder diffraction shows that the Ho moments retain local $\langle 111\rangle$ Ising anisotropy and form spin-in/spin-out configurations on the tetrahedral network. In ${\mathrm{Ho}}_2{\mathrm{Ti}}_2{\mathrm{O}}_7$, real- and reciprocal-space analyses show a nearly ideal 2-in/2-out spin ice state at 0.3 K, with $\sim 95\%$ of tetrahedra satisfying the ice rule, followed by progressive thermal disordering on warming. In ${\mathrm{Ho}}_2{\mathrm{TiO}}_5$, most tetrahedra are magnetically incomplete because some tetrahedral vertices are occupied by nonmagnetic Ti rather than Ho; nevertheless, the dominant incomplete configurations are 2-in/1-out and 1-in/2-out, which are locally compatible with the ice rule if the missing Ho spin is restored. ${\mathrm{Ho}}_2{\mathrm{TiO}}_5$ is therefore a vacancy-disrupted spin ice in which the local $\langle 111\rangle$ Ising character and short-range spin-in/spin-out correlations persist on a topologically incomplete magnetic network, while collective ice-rule correlations are strongly disrupted.

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• Magnetic order
• Pyrochlores
• Spin ice
• Neutron diffraction