Costa joined Chelsea from Atletico in 2014, before returning to the La Liga club in 2017
Atletico Madrid forward Diego Costa is to face trial on 4 June for tax fraud.
According to a court filing, Costa, 31, defrauded the state of more than 1m euros (£813,000) by not declaring payments of more than 5.15m euros (£4.19m) from his 2014 move to Chelsea.
In addition, he did not declare more than 1m euros in image rights.
Prosecutors in Madrid want the Spain international to be given a six month prison sentence and a fine of 507,208 euros (£457,128).
Spanish law allows sentences below two years for non-violent crimes to be exchanged for a fine, so if found guilty Costa would avoid prison if he paid an additional fine of 36,500 euros (£32,896).
Costa re-joined Atletico from Chelsea in 2017.
The amounts Costa is alleged to have defrauded the Spanish government in 2014 are accurate using the currency exchange rates at the time.