The spot highlights the fact that the retailer is the official tailor to the England team, and uses the hashtag #LuckyWaistcoat. It was created in-house by M&S, with media handled by Mindshare.
M&S later ran large digital ads reading "Bring it home" and #LuckyWaistcoat at Wembley Stadium, where it held its AGM this morning.
It follows M&S declaring last Saturday, the day of England's quarter final victory over Sweden, as "National waistcoat day".
Good Morning! Ahead of the big game today, show your support for @GarethSouthgate and the #Eng boys by wearing your #luckywaistcoat on #NationalWaistcoatDay Send us a pic of you wearing yours! #WorldCup #ENGSWE #itscominghome pic.twitter.com/HIlJnpX1Wv— M&S (@marksandspencer) July 7, 2018
Elsewhere, blood cancer charity Bloodwise is using the hashtag #WaistcoatWednesday to encourage fans to imitate Southgate's sartorial elegance and raise money to fund their research.
M&S announced at the start of the month that interest in Southgate's outfit on the touchline had caused waistcoat sales to increase 35%.
There has also been a surge of interest in waistcoats on Google, with searches rocketing since the start of the World Cup.