The star took to Instagram after the show to share a video of the frock on its hanger, writing: "Forgot to take a pic in the studio! Today's zip back, check dress on @thismorning is from @marksandspencer."
Ruth's latest pick is the 'Checked Tailored Dress' from the beloved British brand, which features figure-flattering ruched detailing at the waist, a pretty scoop neckline and three-quarter length sleeves.
Ruth looked gorgeous in her M&S pencil dress
Sadly, the dress has sold out already, though there are some very similar options still available, including the 'Jersey Checked V-Neck Tailored Dress' which is made in a similar fabric.
WATCH: Ruth and Eamonn were in stiches on the show - find out why
The 'Checked Knee Length Skater Dress,' £39.50, would also make a gorgeous option.
As usual, fans were quick to comment on Ruth's on-screen outfit, and she was flooded with compliments on her post.
SHOP SIMILAR: Jersey Checked Tailored Dress, £45, Marks & Spencer
"I thought it looked lovely and flattered your curves in all the right places," one wrote, while another commented: " Such a nice dress and you looked absolutely stunning!"
A further added: "Beautiful on you Ruth."
Ruth and husband Eamonn seemed to have a great time hosting the show as usual – and had a hilarious interview moment during the episode.
Ruth and Eamonn had a giggle on Friday's show!
The couple were chatting to American mother Christy Hagedorn, who was joined by her toddler son Cade at home in Maryland – and he had Ruth and Eamonn in stitches after he made an unexpected reference to his mum's cleavage!
Viewers at home took to Twitter to share their love for Cade, with one writing: "Cade is giving me life on #ThisMorning this kid is soo funny!" "This kid is hilarious," another tweeted, while a third posted: "Hahahaha what a little legend."
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