Without a defined budget, what did the Spanish Inquisition mainly use to finance itself?

Without a defined budget, the Spanish Inquisition mainly financed itself through confiscated goods. Property taken from people prosecuted by the tribunal helped pay for the institution’s operations and personnel.

Confiscation normally began when an accused person was arrested: the notario de secuestros inventoried the suspect’s possessions. If the case resulted in condemnation, those assets could be absorbed by the Inquisition or transferred through royal and institutional channels. This arrangement made the tribunal unusually dependent on the wealth of those it prosecuted.

The financing system created serious conflicts of interest. Critics argued that inquisitors had a financial incentive to target prosperous suspects, especially wealthy conversos. Contemporary complaints repeatedly connected persecution with property seizure, although the scale and destination of confiscated wealth varied across periods and tribunals.

Confiscations should not be confused with ordinary church tithes or a stable state appropriation. The Inquisition was tied closely to the monarchy and could receive support through royal arrangements, but its distinctive financial base was the seizure of defendants’ property. That is why “confiscated goods” is the canonical answer.