The deal has been reached between the 28-nation bloc and Ankara to close the main route by which a million people poured across the Aegean Sea to Greece in the last year.
The deal has been slammed by refugee agencies as well as human rights campaigners. As part of the agreement, Ankara has agreed to take back all migrants and refugees who enter Greece illegally, including Syrians. In return, the EU will admit thousands of Syrian refugees directly from Turkey and rewarding it with more money, early visa-free travel and progress in its EU membership negotiations.
Two Turkish-flagged passenger boats with 131 migrants arrived in the Turkish town of Dikili early on Monday, accompanied by two Turkish coast guard vessels with a police helicopter flying overhead.
A coastguard official on the Greek island of Chios said that 66 migrants, most of them Afghans, were also sent to Turkey on a third boat early on Monday.
On Monday, 47 men were intercepted by the Turkish coast guard on Monday and taken to a holding center next to Dikili's port.
The EU has agreed to resettle thousands of legal Syrian refugees directly from Turkey - one for each Syrian returned from the Greek islands.
Some police and immigration officials were seen waiting outside a small white tent on the quayside at Dikili as the migrants disembarked one by one. All the migrants were photographed and their fingerprints were taken for security screening.