"We never lied," 50-year-old club president, Josep Maria Bartomeu told his first news conference.
A day after former president Sandro Rosell resigned because of a judicial wrangle over the Neymar deal, Bartomeu said the player's father had given permission for previously confidential details of the transfer to be made public.
The Neymar transfer cost €57.1 million euros, plus a €2-million-euro bonus if the 21-year-old international makes the finals of the FIFA World Player of Year award, footballing business manager Raul Sanllehi told the news conference.
In addition, Neymar gets an annual salary of €11.3 million euros to be paid over five years, he said.
Barcelona said the Brazilian was drawn not by money but by the lure of the club and its star, Lionel Messi.
"The player decided to come to Barca with a lower offer than he could have obtained from other clubs because he was very excited to come," Sanllehi said.
Barcelona said the entire deal cost €86.2 million: €57.1 million for the transfer, €10 million euros in a signing bonus, €2.7 million in commissions, €4.0 million in marketing, €2.5 million for Neymar's foundation and €9.9 million in scouting and collaborative deals.
Barcelona's new boss said Neymar's father agreed to let the club reveal the figures because he believed the scandal over the signing was "unfair".
"He repeated that many people have not forgiven his son Neymar Junior for coming to Barcelona rather than going to other teams and accepting more generous offers," Bartomeu said.
Rosell resigned , a day after a judge agreed to hear a case made against him by one of the club's own members for alleged misappropriation of funds in the deal which brought Neymar to the Camp Nou last year.
Rosell had routinely insisted that Neymar cost the club €57.1 million but refused to divulge details on confidentiality grounds.
That led club member Jordi Cases to launch the case against Rosell last month for not informing the club's members as €40 million of the fee was supposedly paid to Neymar family firm N&N.
The club were subsequently asked to submit the contracts that sealed the player's arrival in Catalonia, as well as Barca's financial accounts for the past three years.
And the judge, Pablo Ruz, decided that the documentation handed over reveals "sufficient elements" for an investigation to go ahead.
Barcelona's break down of the €57.1 million transfer cost showed €40 million euros went to the Neymar family firm N&N, and €17.1 million was devoted to the transfer from Santos FC.
Neymar's salary amounted to a total of €56.7 million over five years and was comprised of a total €10 million signing bonus, a €44 million salary and a commission of €2.7 million.