Returned Mail API can be queried using both JSON and XML.

JSON

Query current list of returned mail since last reset and without address:

http://easymail.com/publicinterface/returnedmail.json?account=ABC12345

Query current list of returned mail since last reset including address:

http://easymail.com/publicinterface/returnedmail.json?account=ABC12345&address=true

Query current list of returned mail (since last reset) and reset(clear) list:

http://easymail.com/publicinterface/returnedmail.json?_method=PUT&account=ABC12345&reset=true

JSON Response

[{
	"customer_reference": "123456789",
	"epid": "ZZ4RBR76CMF24YPK464CCW4XR6ZZ",
	"idx": 40,
	"dbid": 99999999,
	"reason": "Not Advised By Mail Carrier",
	"returned_posix": 1499832000,
	"returned": "12/07/2017",
	"received": "25/05/2017"
},
{
	"customer_reference": "012345678",
	"epid": "ZZGYFB639R3RMX6T46MQY2FRYYZZ",
	"idx": 63,
	"dbid": 99999999,
	"reason": "Left Address / Unknown",
	"returned_posix": 1499832000,
	"returned": "12/07/2017",
	"received": "15/06/2017"
}]

XML

Query current list of returned mail since last reset and without address:

http://easymail.com/publicinterface/returnedmail.xml?account=ABC12345

Query current list of returned mail since last reset including address:

http://easymail.com/publicinterface/returnedmail.xml?account=ABC12345&address=true

Query current list of returned mail (since last reset) and reset(clear) list:

http://easymail.com/publicinterface/returnedmail.xml?_method=PUT&account=ABC12345&reset=true

XML Response

<ListReturnsResult>
	<ReturnedLetter>
		<CustomerReference>123456789</CustomerReference>
		<Reason>Not Advised By Mail Carrier</Reason>
		<EPID>ZZ4RBR76CMF24YPK464CCW4XR6ZZ</EPID>
		<index>40</index>
		<ReturnedDate>12/07/2017</ReturnedDate>
		<BingDBID>99999999</BingDBID>
		<ReturnedPosix>1499832000</ReturnedPosix>
	</ReturnedLetter>
	<ReturnedLetter>
		<CustomerReference>012345678</CustomerReference>
		<Reason>Left Address / Unknown</Reason>
		<EPID>ZZGYFB639R3RMX6T46MQY2FRYYZZ</EPID>
		<index>63</index>
		<ReturnedDate>12/07/2017</ReturnedDate>
		<BingDBID>99999999</BingDBID>
		<ReturnedPosix>1499832000</ReturnedPosix>
	</ReturnedLetter>
</ListReturnsResult>