How Does Social Security Affect Farmers’ Contracted Land Withdrawal: Evidence from the Suburbs of Shanghai and Wuhan

The withdrawal of rural households from contracted farmland optimizes land resource allocation, aligning with urbanization and agricultural modernization goals, and supports agricultural transformation and urban–rural integration. Utilizing survey data from 1478 rural households in Shanghai and Wuhan suburbs, this study employs ordered Probit models and mediation effect tests to examine how urban social security influences farmland withdrawal and the role of pension income. Results indicate that within the context of new urbanization, 56.90% of rural households exhibit a social security participation rate exceeding 50%, with urban social security enrollment significantly facilitating the withdrawal of contracted farmland by suburban rural households. Specifically, a one-unit rise in the proportion of insured individuals escalates the likelihood of permanent farmland withdrawal by 25%. Among these, pension income plays a positive mediating role in the process of urban social security influencing farmers’ withdrawal from farmland. Participation in urban social security enhances farmers’ pension income levels, thereby strengthening their farmland withdrawal degree. Consequently, to effectively advance the mechanism for rural farmland withdrawal, social security emerges as a fundamental pillar. This study furnishes empirical backing for the “substituting land security with social security” proposition and offers crucial insights for enhancing rural land withdrawal policies.