Blatter, who led FIFA for 17 years, was cleared of fraud by the Federal Criminal Court in the southern city of Bellinzona.
Platini, a former France national team captain and manager, was also acquitted of fraud.
The two, once among the most powerful figures in world football, had denied the charges against them.
Prosecutors had accused Blatter, who led FIFA for 17 years, and Platini of unlawfully arranging for FIFA to pay the Frenchman two million Swiss francs (£1.7m) in 2011.
The case meant Blatter ended his reign as FIFA president in disgrace and it wrecked Platini’s hopes of succeeding him after he was banned from football when the affair came to light.
Blatter had said the payment followed a “gentlemen’s agreement” between the pair when he asked Platini to be his technical advisor in 1998.
Platini worked as a consultant between 1998 and 2002 with an annual salary of 300,000 Swiss francs (£257,000) – the most FIFA could afford because of money troubles the organisation had at the time, Blatter had told the court.
The rest of Platini’s one-million per year salary (£857,000) was to be settled at a later date, Blatter said.
Motives for the payment were unclear, although the two men met in 2010 and discussed the upcoming elections for the FIFA presidency in 2011.
When Blatter approved the payment he was campaigning for re-election against Mohamed bin Hammam of Qatar. Platini, then president of UEFA, was seen as having sway with European members who could influence the vote.
The payment emerged following a huge investigation launched by the US Department of Justice into bribery, fraud and money laundering at FIFA in 2015, which triggered Blatter’s resignation.
Both officials were banned from football for eight years in 2015 over the payment, although their bans were later reduced.
Platini, who also lost his job as UEFA president following the ban, said the affair was a deliberate attempt to thwart his attempt to become FIFA president in 2015.
Platini’s former general secretary at UEFA, Gianni Infantino, entered the FIFA race and won the election in 2016.
Speaking following the verdict, Platini said: “I want to express my happiness for all my loved ones that justice has finally been done after seven years of lies and manipulation.”
He added: “My fight is a fight against injustice. I won a first game.
“In this case, there are culprits who did not appear during this trial. Let them count on me, we will meet again. Because I will not give up and I will go all the way in my quest for truth.
“Believe me, going from being a legend of world soccer to a devil is very difficult, especially when it unfairly comes to you.”
A statement from the Swiss Attorney General’s Office in response to the verdict said:
“The Office of the Attorney General of Switzerland (OAG) has taken note of the decision of the Criminal Chamber of the Federal Criminal Court. Once the Court has issued the written reasoning of its decision, the OAG will decide about how to further proceed.”