Kinahan was convicted of 10 counts of money laundering in Belgium in 2009 but was allowed to return to Spain after lodging an appeal.
He was arrested on 6 July in Estepona on the Costa del Sol on a warrant issued by the Belgian judicial authorities.
Kinahan agreed to be extradited when he appeared before a judge at Madrid’s National Court two days later.
However, he was held in a Madrid gaol for more than a month while the judge considered the request from Belgium.
The extradition was delayed because Kinahan is being investigated in Spain over claims he ran a massive drug trafficking and money laundering organisation.