Both clubs had successful pre-season campaigns, with Slough going unbeaten - but that counted for little at Arbour Park as Marcus Law's Poppies dominated the opening 45 minutes and kept the home side at bay when they put in an improved second half showing.
The opening exchanges were, perhaps predictably, even with both sides feeling their way into the new season. Kettering left-back James Brighton had two efforts from free kicks, one easily saved by Jack Turner and the other sent over the bar.
Despite not threatening the Slough goal, Kettering started to dominate the play - pressuring the home side into mistakes and winning challenges - and the Rebels struggled to gain any kind of momentum.
Kettering deservedly took the lead on 27 minutes. A free kick conceded by George Wells out wide on the touchline was swung into the box by the left foot of Brighton, and Poppies skipper Brett Solkhon flicked a header into the far corner giving Turner no chance.
Just a minute later, it was very nearly two as Matthew Stevens broke down the right and crossed low, but just in front of the onrushing Ben Milnes.
Rene Howe saw an effort well blocked as the Poppies kept up the pressure on Slough’s goal, and the visitors almost doubled their lead a minute before the interval, but Turner kept out a header from Milnes with a fine reaction save.
Slough introduced Manny Williams at half time in place of Nathan Smart in an attempt to turn things around, and the Rebels immediately livened up. Matt Lench headed wide from a long throw - the home side's first effort - and later he shot wastefully wide after Williams sprinted through on goal, rounded goalkeeper Paul White and squared it to him.
But at the other end, Kettering went close again with Stevens beating several challenges but firing wide, appearing to slip as he did so.
Warren Harris had a long shot spilt by Paul White with neither Chris Flood nor Harris able to create a chance from the rebound.
Turner kept out a dipping shot from distance and substitute James Dobson stung the palms of White, but Slough's attempts looked to be in vain. Kettering nearly doubled their lead on 75 minutes, but Howe fired over from six yards after Turner struggled to hold onto a header across goal.
But with a minute remaining, Kettering looked to have wrapped up the three points as Milnes beat Turner after being fed by substitute Gary Stohrer following a clinical attack on the break.
Dobson's 25-yard thunderbolt in added time was the home side's brightest moment by far, but came too late to make a difference to the result.
Slough joint manager Jon Underwood acknowledged his side were second best throughout when speaking with John Porter after the match.
"We've had a perfect pre-season and then when it matters we've been found wanting.
"Kettering were a yard ahead of us mentally, and passed it better than we did. We ended up having to change our shape after half an hour as a result.
"We showed more endeavour in the second half but didn't hurt them enough."
Kettering Town Line up
Paul White, Durell Berry, James Brighton (Rhys Hoenes 67), Brett Solkhon (c), Gary Mulligan, Michael Richens, Liam Bateman, Matthew Stevens (Gary Stohrer 82), Rene Howe, Ben Milnes (Munashe Sundire 90), Lindon Meikle. Subs not used: Ben Baker, Ben Toesland.