Some 14,000 migrants returned to their home countries from Greece since the beginning of 2017, abandoning hopes of legal passage and asylum in wealthier parts of Europe.
According to Greek police figures released on Thursday, in September alone 1,598 people returned with assistance from the International Organisation for Migration (IOM).
The returnees were mostly Albanians, Afghans, Pakistanis, Iraqis, Georgians and citizens of northern African countries.
Tens of thousands of refugees and migrants were stranded in Greece after Balkan countries closed their borders to them in April 2016.
Before that, more than one million people had reached western Europe from Turkey, across Greece, Macedonia, Serbia, Hungary or Croatia and Slovenia.
The returnees travel back under protection and receive between 500 euros and 1,500 euros (590-1,760 dollars) in IOM assistance.