Celebrating four decades in television, the This Morning presenter wrote: "My journey in TV all began in Oct 1980. 40 years ago this very month with my beloved Ulster Television. It seems like yesterday. So Happy Anniversary to me [cake emoji].
"Plenty more chapters to write I hope. Thank you for being there and I hope you'll be with me in the future too." Upon seeing the post, doting wife Ruth remarked: "Happy Anniversary gorgeous! [lips emoji]."
WATCH: Find out what word this toddler said to make Ruth and Eamonn howl with laughter
Friend Rochelle Humes commented: "You are a legend. Happy Anniversary Mr H." Alison Hammond: "The best in the biz!!!! Happy Anniversary Eamonn." To which, Eamonn replied: "Awww... but then I always say you should get out more often!"
Belfast-born Eamonn kicked off his career at the age of 21 when he joined Ulster Television, the Northern Ireland franchise of ITV back in 1979. A few years later, he went on to present the news for their flagship show Good Evening Ulster.
Eamonn posted this throwback snap on Instagram
He also co-presented GMTV for twelve years between 1993 and 2005, before hosting Sky News Sunrise for eleven years between 2005 and 2016. Now, Eamonn, 60, hosts This Morning alongside Ruth, also 60, every Friday.
The couple have previously opened up about their working relationship while talking to HELLO!. Ruth said: "The challenges are what everyone faces when they work together, it's like two people who want to drive a car and one wants to go left and one wants to go right, and you have to compromise.
Eamonn and Ruth work together on This Morning
"And you know, Eamonn's not a team player really – he likes to be out there doing his thing. And he has to compromise and work with me so it's a challenge all the time."
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