We characterise the rental subsidy use in units developed with construction subsidies and explore whether such concurrent subsidy use responds to needs unmet by a tenant-based programme alone. We develop a typology of households to guide our analysis focusing on voucher use in Low Income Housing Tax Credit (LIHTC) units. Findings for Ohio in 2011 suggest that the use of additional rental assistance in LIHTC can be complementary in serving certain high-need populations, particularly when targeted housing services are provided. Very poor households with special housing needs constitute over 60% of the population with additional rental assistance in LIHTC, yet the extent to which additional housing services are provided to them is unclear. However, our analysis identifies a significant portion of households in LIHTC units that could seemingly be housed in the private rental market, signalling some degree of inefficiency in the current subsidy mix. While we find that very low income voucher holders are more likely to use their voucher in an LIHTC unit when facing a tighter market or a potential gain in neighbourhood quality, the effects are small.