Carlos Tevez, David Silva and Yaya Toure were also on target against a lacklustre Newcastle outfit, who remain not quite far enough clear of the drop zone for comfort.
With potential back-to-back games against Manchester United looming, little wonder why City manager Roberto Mancini was so concerned at Belgium's use of his captain, who was returning to club duty for the first time in two months after a calf problem.
For Kompany is going to be a key man over the next fortnight, which could do so much to determine whether Mancini's work over the season is viewed as progress or inexcusable regression.
They may have been in the top two for five months but the title fever that gripped City at this point last season is nowhere to be seen and news of the Manchester United win at Sunderland that briefly took the Red Devils 18 points clear was greeted with complete indifference in the stands.
The large section of Roberto Mancini's programme notes devoted to the FA Cup semi-final, a match not due to take place for another fortnight, seemed to indicate where the priority now lies, beyond, of course, securing a Champions League berth for next season.
For 20 minutes it appeared the minds of Mancini's players were drifting towards a meeting with Chelsea or United at Wembley on April 14 too.
The liveliest the home fans got was with Newcastle goalkeeper Rob Elliot, who from a ridiculously early point was dragging out every dead ball and free-kick he was asked to take.
As it turned out, the game clicked into gear thanks to a rare visitors' attack. Vurnon Anita dropped a superb crossfield pass perfectly into the path of Papiss Cisse, whose first-time effort was well saved at his near post by Joe Hart.
Within minutes Gareth Barry was striding onto Samir Nasri's cut-back, the goal gaping in front of him. Inexplicably, Barry fired over, eliciting groans from the home faithful who were expecting so much more from their team, both on Saturday and in the season as a whole.
Crucially though, City had built up some momentum. And when Gael Clichy squeezed a cross through to the far post, Tevez slid in to turn it home.
It was the South American's seventh goal in six games and his 17th overall this season, and the hosts were in no mood to offer Newcastle any way back.
Clichy brought an outstanding save out of Elliot, as did Edin Dzeko, before an intricate bit of passing from Yaya Toure and Samir Nasri offered Silva the chance to reach the corner of the six-yard box, where he buried his shot with some aplomb.
Why Newcastle waited until their position was virtually hopeless before injecting any degree of urgency into their game was a mystery but they began the second period with a sense of purpose so obviously absent during the first half.
Yohan Cabaye flashed a shot across goal after running onto Cisse's lay-off before the midfielder zipped a shot over from 20 yards. In between, an offside flag rendered Cisse's shot over on the stretch irrelevant.
That flurry was as good as it got for the visitors. And there could be no more appropriate scorer of City's third goal than Kompany.
His last for the Blues was the goal that won the derby in April 2012. This was not quite in the same class, the Belgian flicking home an off-target Barry effort that hit two Newcastle men besides.
In the whole scheme of things, it will matter little. However, it offered the home fans an opportunity to train their thoughts on what could be the first of two successive meetings with United, depending on Monday's FA Cup replay, at Old Trafford on April 8.
On this form, Sir Alex Ferguson's side will find it difficult to confirm their superiority. With 20 minutes left, Toure strode through some poor Newcastle defending and beat Elliot at his near post with a shot that deflected off James Perch.
Toure's effort was the signal for Sergio Aguero's return from injury, in place of Samir Nasri, which is also good news for City ahead of the derby, when the Blues will look to delay an inevitable 20th title - which now cannot be won until April 17 at the earliest - for another couple of games.