The skipper, in his tenth campaign with the Blues and now officially our most successful captain of all time, was ecstatic after the news broke that City had won the title following United's shock home defeat to West Brom.
Jay Rodriguez's second half header for bottom of the table Albion sparked wild celebrations among City players and fans across Manchester.
Word quickly got around through social media and City fans queued outside a venue still advertising United's televised clash with the Baggies in a bid to join fellow supporters inside, where the players were seen belting out Oasis' Wonderwall and being serenaded by supporters expressing their delight and gratitude.
"Today was a day for the Blues - there have been many days for the Reds before, and ultimately it's banter".
City provided a live stream of the Belgian's reaction at the full-time whistle, with Kompany facetiming his colleagues Kevin De Bruyne and Kyle Walker and keeping his fingers busy in the squad Whatsapp chat.
The 32-year-old has featured in all three of City's Premier League triumphs, as well as their FA Cup and League Cup victories.
"People are asking whether we are the best Premier League side in history, but the answer is no, because we have a lot of work to still do", he told City's official website. I suppose the team-mates will perhaps roll their eyes a little bit but I have never retained a title so I want to see how we react now next season.
Man City crowned 2017-18 Premier League champions
They can surpass Chelsea's Premier League record of 30 (2016-17) by winning three of their remaining five fixtures. Wins over West Ham and Southampton would give them 50, and have Pep's men holding yet another record.
However, Kompany was glued to the action, even if he found it hard to watch his team's destiny in someone else's hands.
"I had a feeling when I woke up this morning", he said.
Guardiola is the first Spaniard to manage a team to the English top-flight title.
Kompany indicated he spoke with the same voice as Guardiola, who can now lay claim to 24 trophies in a nine-year coaching career which includes triumphant spells at Barcelona and Bayern Munich.
It completes an impressive revival from City, who failed to win a single prize previous year.
Kompany has overcome persistent injury problems in recent seasons to remain a part of Pep Guardiola's plans.
"I have learnt from him". If I had met Pep when I was 20-years-old I would have been the flawless player for him and would have been able to improve so much, ' the Belgian defender added.