In this paper we analyze criteria for robustness of non-locality of symmetric states. We develop our research using the recently developed extended Hardy’s paradox non-locality test. We investigate the case of symmetric states, we show that for high numbers of qubits the non-locality of W state can tolerate high degree of noise. We also demonstrate that the choice of the bases is, in particular cases, an important criterion for robustness independently from the bases which give high violation. We also apply our techniques to a discrimination of entanglement class.