In this study, we analyzed how household income impacts the tenure decision based on the type of housing. Considering the recent growth in the market for high monthly rents, it is anticipated that household income will have diverse effects on the decision between Chonsei or monthly rent. Analysis of the Seoul Housing Survey 2019 suggests that when keeping all other factors constant, a rise in household income is likely to result in a preference for monthly rent over Chonsei. An examination of the non-linear impact of income revealed that individuals tend to opt for Chonsei up to a certain income threshold. Beyond this point, a higher likelihood of choosing monthly rent was observed. This shows that the choice between Chonsei and monthly rent varies according to the household income. Household income also has different effects on this choice depending on the housing type. Apartment tenants tend to opt for Chonsei until their income crosses a specific threshold, beyond which higher-income households are more inclined to choose monthly rent. Residents of detached or multi-family houses tend to favor monthly rent as their income increases. Once their income surpasses a certain threshold, they become more prone to selecting Chonsei. This validates the hypothesis of differentiation in choosing Chonsei or monthly rent as this choice by tenants is not indiscriminate but is affected by the financial situation of households. The results of this study show that the monthly rent market cannot be regarded as a single market, and it must be classified by housing type and price. Moreover, the choice of monthly rent by higher-income households may vitalize the market for private rental housing. The choice of monthly rent made by lower-income groups living in detached or multi-family houses because of financial constraints must be approached via policy to reduce the burden of housing expenses.