The forward had accepted four counts of tax fraud worth £12.9m and using shell companies to hide around £25m from image rights.
Cristiano Ronaldo has accepted a £17m fine and a suspended two-year jail sentence following allegations of tax evasion in Spain.
The former Real Madrid forward, 33, appeared in court in the Spanish capital on Tuesday morning.
The Portugal international had already agreed a deal to pay the fine after pleading guilty last year to charges brought by Spanish state prosecutors and tax authorities.
He appeared relaxed as he arrived at court with his Spanish fiancee Georgina Rodriguez, smiling and signing an autograph on his way in.
Judges had refused his request to appear by video or to enter court via a back entrance.
Ronaldo – who currently plays for Italian side Juventus – spent around 45 minutes in the court building but his hearing lasted only a few minutes.
After formally accepting the deal offered by prosecutors, he signed the agreement to pay the fine of nearly €19m (£16.7m).
The charges stem from his nine years at Real, who he left last summer.
Prosecutors accused him of four counts of tax fraud from 2011-14 worth €14.7m (£12.9m) and using shell companies outside Spain to hide around €28.4m (£25m) made from image rights.
The prosecutor also alleged he falsely reported income as coming from real estate, which it said had greatly reduced his tax rate.
Last year, Celebrity Net Worth estimated Ronaldo was worth around $450m (£354m), with an annual salary of about $57m (£44m).
According to Forbes he earned $93m (£72m) in 2017, making him the world’s third highest-paid athlete behind boxer Floyd Mayweather and long-time football rival Lionel Messi.
A custodial sentence would have effectively ended his career, but that was not considered likely as, in Spain, a judge can suspend sentences for two years or less for first-time offenders.
He will not serve any jail time unless he commits a further offence.
Ronaldo is one of the most successful footballers of the 21st century, having won five league titles with Manchester United and Real, five Champions League titles, and five Ballon d’Ors, awarded to the best player in the calendar year.