This article questions the drivers behind the distribution of savings in different capital markets in Portugal between 1550 and 1800. A novel dataset of credit transactions, interest rates and debt service documents a shift in the lenders' investment behaviour. By 1712, one of the leading institutional creditors—the Misericórdias—had ceased to allocate funds to the sovereign debt market. Data reveal that this disinvestment was neither related to the poor performance of debt service nor to the lure of potentially higher returns on private credit. We argue that changes in the rationales for issuing debt justify the drop in the number of institutional investors in the public credit market, and this correlates with the heavy allocation of funds into private lending.