Vaxevanis, the publisher of Hot Doc magazine,could be in court again as early as next month.
The public prosecutor claims to have found "legal faults" in the original verdict passed on 1 November.
"This is an unprecedented decision that drags the country through the mud, muzzles the press and serves [vested] interests," Vaxevanis said in a statement to the AFP news agency.
The 46-year-old journalist will now be tried by a panel of three judges, the source said on condition of anonymity.
A single judge presided over the first hearing.
Vaxevanis faces a maximum three-year prison sentence for publishing a document containing the names over 2,000 Greek HSBC account-holders in Switzerland.
The list was originally leaked by an HSBC employee and passed to Greece in 2010 by France's then-finance minister Christine Lagarde, who now heads the International Monetary Fund.
The list enabled authorities in France, Spain and Britain to recuperate millions of euros in lost tax revenue but Greek authorities treated it as stolen data and failed to pursue the case.
None of the people named by Vaxevanis have pressed charges against him and his first trial caused widespread indignation.
The affair has resurfaced amid British press reports over another list of some 8,500 people with accounts at the HSBC branch of the Channel Island tax haven of Jersey.
Greek Finance Minister Yannis Stournaras on Thursday wrote to his British counterpart George Osborne to request information on the list, which reportedly includes nearly 100 Greek account-holders.