A tourbillon mechanism for a timepiece movement includes a balance mechanism, an escapement mechanism and a carriage mounted in a structure of the timepiece movement in rotation about a tourbillon axis. The balance mechanism includes a spring and a balance wheel mounted in the carriage to pivot about the tourbillon axis. The escapement mechanism includes an escape wheel with teeth and a pallet-lever including pallet-stones configured to engage the teeth, the pallet-lever being mounted in the carriage and coupled in rotation to the carriage by a pivot device. The escape wheel encircles the tourbillon axis and is attached to or integral with the structure of the timepiece movement.