Tesouro Direto is a program run by Brazil's National Treasury (Tesouro Nacional) that lets anyone buy federal government bonds — in other words, lend money to the Federal Government in exchange for a return. Because they are issued by the government, these bonds are considered the lowest-risk investment in the country.

Yes. Tesouro Direto bonds are backed by the sovereign guarantee of the Federal Government, through the National Treasury, which issues the bonds. In practice, this means the government itself guarantees payment of the invested amount plus interest at maturity.

This is considered the strongest guarantee in the Brazilian market: for payment to fail, the Federal Government would have to default on its own debt — something that has never happened in the history of the program.

Tesouro Direto is not covered by the Credit Guarantee Fund (FGC), and this does not mean higher risk. The bonds don't need the FGC because they already carry a stronger guarantee: that of the Federal Government itself.

The FGC protects products issued by banks and financial institutions (such as CDB, RDB, LCI, and LCA) against the failure of those institutions. Tesouro Direto, on the other hand, is issued by the government, which has far greater capacity to raise revenue and issue debt than any bank — which is why the sovereign guarantee is considered even more solid than the FGC's.

Tesouro Direto bonds are custodied at B3 (the Brazilian stock exchange), registered directly under your CPF. This adds an extra layer of security: because the bonds are in your name, they remain yours even if the brokerage you invested through runs into trouble. In that case, the bonds can be transferred to another institution or redeemed directly.