Studies indicate that mortality increases after income receipt. To explore whether this is due to increased economic activity around the period of receiving income, we examine within-month patterns in ambulance transport incidents, focusing on location and timing. Using Japan's National Pension payments made every two months, we compare the number of ambulance transport incidents on the day of pension payment and on surrounding days in payment months with those in non-payment months. The results show a 4.5% increase in ambulance transport incidents on the day of pension payment, linked to increased activities such as gambling, shopping, and dining out. We show suggestive evidence that income receipt boosts economic activities by the mechanism of easing liquidity constraints. These findings have implications for healthcare system preparedness and the optimal design of public benefit payment.