The court, presided over by Judge Salvatore Capelleri, also agreed that Armani should pay 100 million lire ($64,000) as part of the plea bargain, a formula that implies admission of wrongdoing in exchange for leniency and a quick ruling.
Armani said in a statement issued after the judge's ruling that he did not consider himself guilty.
"I decided to plea bargain, even though I don't believe I am guilty of this charge, in order to close a chapter that has upset my professional serenity." he said. "I gave up the opportunity to explain before the judge the reasons which, I am confident, could have cleared me."
Court sources said Armani, accused of paying 100 million lire to Milan tax inspectors in exchange for lenient audits on his fashion house, had repaid the money. He has said in the past that the money was extorted from him.
Eight other defendants, including Aldo Pinto, whose wife, Mariuccia Mandelli, is better known as the designer Krizia, were granted their requests for plea bargains.
The 10 remaining defendants, including top designers Gianfranco Ferre, Krizia and Gianni Versace's brother, Santo, declined to bargain. Their lawyers told reporters that they wanted to be able to clear their names.
A total of 19 designers, industry associates and tax inspectors are on trial. None were in the Milan court yesterday.
Armani's lawyer, Lionel Ceresi, said earlier his client sought the plea bargain as a "mechanism for simplification".
"We would not want any negative publicity to absorb Mr Armani's positive publicity and that's why we opted for a plea bargain," said Ceresi.
"Mr Armani's work is creative and he can't be distracted by the trial process which is made worse by the press."Reuse content