We rent the Ertiga. We do not rent the Innova. You should read what follows knowing that, and you should also know that we turn down bookings on this basis several times a month.
The two cars are close enough in seat count that people treat them as interchangeable and far enough apart in size that they are not.
The short answer
Four or five people, up to about four hours: the Ertiga, comfortably. You will pay meaningfully less per kilometre and give up nothing you will notice.
Six adults, or any trip beyond about six hours with a full car: the Innova. The extra is not a luxury at that point, it is the difference between arriving fine and arriving sore.
Everything else is detail on those two lines.
Where the real difference is
It is not the seat count — both are marketed as seven-seaters, both mean six passengers plus a driver in practice.
It is the third row, and it is time-dependent. The Ertiga’s third row is genuinely fine for two adults for two or three hours. Past that, the seat base is low and knee room is limited, and what was acceptable becomes something people remember. The Innova’s third row is usable for longer, though nobody should pretend it is the best seat in either car.
And it is luggage with a full car. With all seats occupied in either vehicle you are down to the space behind the third row. In the Ertiga that means cabin bags. In the Innova there is more, though still not a lot. If you have six people and six large suitcases, neither of these is your answer.
Where the Ertiga wins outright
Cost per kilometre. Over a long round trip the gap is substantial, and for four people it buys nothing you will use.
Narrow roads. On a ghat with tight hairpins, or in an old temple town’s streets, the smaller car is easier to place and less stressful for the driver — which you feel as a passenger.
Ride on ordinary surfaces. The Ertiga is softer on the sort of imperfect tarmac that makes up most of a South Indian journey.
Where the Innova wins outright
Six adults for a long day. No argument.
Rough roads and high clearance. A body-on-frame vehicle deals with broken surfaces and unmade approaches better.
Perceived status. This matters for weddings and for some corporate travel, and pretending otherwise is silly.
The test we actually use on the phone
Two questions:
How many people, honestly? Not “six or seven” — the real number, including the ones who might join.
How many hours in the car, in one go? Not the distance. The hours.
Six people and six hours, and we will tell you to book something bigger. That is not modesty; it is that we would rather lose a fare than earn a complaint about a cramped third row, which is the review that costs us the next ten bookings.
If the answer is the Ertiga
The car is described in full here, including the boot figures and what the third row is actually like. Rates are published, and every route page works out the fare for that specific journey.
If the answer is not the Ertiga, tell us the group size anyway — we operate as part of a wider fleet and will put you in the right vehicle rather than the one we happen to be selling.