PI tomography is commonly used in experiments involving permutationally invariant states. If the density matrix ϱ ϱ P I obtained by PI tomography is entangled, then density matrix of the system, ϱ ϱ is also entangled. For this reason, the usual methods for entanglement verification, such as entanglement witnesses or the Peres-Horodecki criterion, can be applied to ϱ ϱ P I . Remarkably, the entanglement detection carried out in this way does not assume that the quantum system itself is permutationally invariant.