After Caria's sudden death, Bustianu Cumpostu was elected new leader by defeating Gavino Sale, who would lead the party's left-wing faction for five years, before leaving in 2001.

In the 1996 general election SN won 4.3% in single-seat constituencies (11.6% in Tortolì and 9.6% in Iglesias), despite being present only in ten constituencies out of fourteen, and 2.3% for proportional representation, due to competition from the Sardinian Action Party (PSd'Az), which gained 3.8%.

[1] In the 1999 Sardinian regional election SN had its best result ever, as Cumpostu received 5.8% of the vote for president, while the PSd'Az gained 8.3% with Franco Meloni.

In the election the Sardist electorate was very fragmented (also because of the presence of the Union of Sardinians, UDS, which ran on a "nationalist" platform) and most of SN former voters voted Sale for President (1.9%) and the iRS party list (0.7%), while only a minority voted for SN (0.4%).

In the 2014 regional election the party unsuccessfully sought to join the coalition led by Michela Murgia (centred on Project Republic of Sardinia), in list with alike separatist parties, and finally decided not to take part to the election.