Exeter beat Harlequins 47-38 in a 13-try final day thriller at Sandy Park.
Will Evans' early try put Quins in front, but three tries in a five-minute spell - while Matt Symons was sin-binned - saw Exeter lead 14-12.
Aaron Morris and Joe Simmonds swapped tries in the final few minutes of the first half before Ian Whitten and Louis Lynagh did the same after the break.
Jack Nowell put Exeter in front, Lewis Gjaltema and Tyrone Green restored Quins lead before Marcus Street won it.
Sam Maunder's try in the final moments added gloss to Exeter's success in front of a record Sandy Park crowd of 14,876.
Defending champions Harlequins had already secured third place in the Premiership before kick-off and will travel to Saracens in the semi-finals, looking to face either Leicester or Northampton at Twickenham.
Exeter end the season six points off the play-off spots in seventh place, the first time they have finished outside the Premiership's top two since 2015.
The feast of attacking rugby began when Evans pounced on a superb kick from Marcus Smith to put Quins ahead in a hotly-contested early period.
Symons was then sin-binned for a deliberate offside with Exeter in close range and Jonny Gray went in from a metre soon after.
Danny Care's excellent grubber kick put Joe Marchant in for Quins' second try, but Exeter struck back again as Hogg went over after a couple of phases following Joe Simmonds' great cross-field kick with the visitors still a man down.
Quins thought they would go into the break ahead after Morris powerfully cut a superb line to score - the returning winger injuring himself in the process.
But Simmonds blasted through after a missed tackle by Green as the first half ended 19-19.
Whitten ended some great forward play for a try six minutes after the break before Smith magically stepped around some Exeter tacklers deep in his own territory and fed Lynagh who sprinted the length of the field to scored a brilliant effort.
But again Exeter went ahead when Dave Ewers' powerful run set up Nowell, but Alex Dombrandt's kick-through to Gjaltema got Quins within two points after a missed conversion.
The champions led again when Dombrandt and Marchant linked well to release Green, but it was the last time Tabai Matson's side would lead as Exeter avenged their defeat in last season's Twickenham showpiece.
First, replacement prop Street went in from close range before Scotland skipper Hogg broke down the left and fed replacement scrum-half Maunder.
Exeter head coach Ali Hepher told BBC Radio Devon:
"It was an up-and-down game wasn't it? But seeing this place packed was pretty special, so it was a ground-breaking day for the club.
"But to come through a tight one like that, sometimes we've let sides back into games and we probably did that again today, but we had enough about us just to see it off.
"I'm pleased with the win. Obviously Quins have got half an eye on next week but, for us, it was important to get a win that gives us confidence to go into the pre-season and attack next season in good spirits."
Harlequins' senior coach Tabai Matson told BBC Radio London:
"You come here and they've got a phenomenal team and they hold the ball anyway, so there's always going to be positive intent, but it ended up being a bit of a festival match.
"If you're standing back looking at it as a fan, really it was entertaining, some really good tries, but I think for us we learnt a lot defensively. That's the big thing we'll take away leading into the semi-final.
"The scoreline doesn't reflect a really good defensive effort, but at times we were really resolute with our defence. But they're a good side and if you make mistakes they punish you - and they did.
"The big thing to be fair, we didn't break anyone and that was probably the big thing, we got through reasonably unscathed."
Exeter: Hogg; Nowell, Whitten, H Skinner, Woodburn; J Simmonds, Townsend; Hepburn, Yeandle (capt), Williams, Gray, Jenkins, Ewers, Vermeulen, Capstick.
Replacements: Harris, Kenny, Street, S Skinner, Witty, S Maunder, O'Brien, Cordero.
Harlequins: Green; Lynagh, Marchant, Esterhuizen, Morris; Smith, Care; Marler, Walker, Collier, Symons, Tizard, Lewies (capt), Evans, Dombrandt.
Replacements: Gray, Els, Louw, Hammond, Chisholm, Gjaltema, Allan, Northmore.
Sin-bin: Symons (17).
Referee: Ian Tempest