The country's Court of Cassation, which rules on questions of law, ruled Tuesday that a trial was justified for Sarkozy as well as his lawyer Thierry Herzog and a former judge, Gilbert Azibert.
That means a trial will now go ahead, according to a source close to the case and one of the defence lawyers. Sarkozy's lawyers were not immediately available for comment.
The influence-peddling case centres on conversations between Herzog and Azibert that were tapped by investigators looking into claims that Sarkozy accepted illicit payments from the L'Oreal heiress Liliane Bettencourt for his 2007 presidential campaign.
They suspect Sarkozy and his lawyer were seeking information on developments in the case, with Sarkozy offering Azibert a plum job in Monaco in exchange.
The inquiry also revealed that Sarkozy and Herzog often communicated via cellphones obtained under false identities – with Sarkozy using the name Paul Bismuth.
He was cleared over the Bettencourt allegations in 2013, and has argued that Azibert never got the Monaco job, meaning he should not have to face trial.
But investigators believe the deal fell through because Sarkozy and his lawyer learned their phones were being tapped.
In 2014, Sarkozy became the first former French president to be taken into police custody during a preliminary stage of the inquiry.
Sarkozy is not the first ex-president to be prosecuted – his predecessor Jacques Chirac was given a two-year suspended sentence in 2011 for embezzlement and misuse of public funds during his time as mayor of Paris.
But he has been dogged by legal investigations since failing in his 2012 re-election bid.
Last month a top court rejected an appeal to avoid another trial, involving charges of illicit financing for the 2012 campaign.
Prosecutors claim Sarkozy spent nearly €43 million on his lavish re-election bid – almost double the legal limit of €22.5 million – using fake invoices.
Sarkozy has denounced the charges, saying he was unaware of the fraud by executives at the public relations firm Bygmalion, who are also among a total of 13 people likely to face trial.