2026/05/28 CRETA Seminar - Taxing Multi-Home Ownership: Affordability and Utilization Effects of Taiwan’s House Hoarding Tax

Title：

2026/05/28 CRETA Seminar - Taxing Multi-Home Ownership: Affordability and Utilization Effects of Taiwan’s House Hoarding Tax

Introduction：

A progressive holding-cost tax on multi-home owners can affect housing markets on two margins: it can lower prices through tax capitalization, and it can reduce vacancy by inducing owners to activate or divest idle units. We estimate this dual-margin response using Taiwan’s House Hoarding Tax, a differential tax on non-owner-occupied residential properties whose staggered local adoption from 2014 onward generates quasi-experimental variation in holding costs. Using staggered synthetic control methods, we document that price-to-income ratios fall by 5.1%–6.2% within two to three years of adoption, while vacancy rates fall by 2.0%–4.6% within one to two and a half years; the utilization response emerges substantively earlier than the price response. The aggregate ATT masks systematic heterogeneity across local housing markets: price effects concentrate in supply-inelastic Taipei, while utilization effects concentrate in more elastic, high-in-migration Taoyuan and Hsinchu County. With only four treated jurisdictions, we interpret this ordering as descriptive evidence consistent with a simple urban-fundamentals framework in which the incidence of holding-cost taxes depends on local supply elasticity and demand pressure. The results show that a single tax instrument can simultaneously affect affordability and housing utilization, with the relative importance of each margin shaped by local market conditions.