The MHK not paying into his pension is North Douglas member John Houghton.
Manx Radio revealed the news had been reported this morning (Thursday).
It brings to an end a media investigation to find out which politician is still not paying into their pension pot.
Yesterday, the Manx Treasury revealed one of the 24 MHKs had not paid since voluntary contributions to the Tynwald members' scheme began in 2012.
Last week, all 24 members assured Manx Radio they have been paying contributions into the Tynwald Members' Pension Scheme.
Mr Houghton told Manx Radio on December 1 that he submitted his form within days of the 2012 Tynwald debate. Manx Radio has made attempts to contact Mr Houghton. Members of Tynwald elected at the last General Election do not legally have to contribute to their pension.