Do the self-employed underreport their income? Evidence from Japanese panel data

This paper examines to what extent self-employed households underreport their income to tax authorities in Japan. To this end, we employ the so-called expenditure-based approach, which essentially compares the current expenditure of self-employed and wage earner households while controlling for their income, net worth, and household characteristics. Using Japanese household-level panel data for the period 2009−2019, we find that the self-employed possibly underreport their income by 33.0–36.4%. Our findings are also robust to the different preferences (degree of risk-loving, time discount rates, etc.), planned retirement age, and degree of measurement error in expenditure between the self-employed and wage earners.