

Roughly half the North Pacific humpback population spends its winter in Hawaiian waters, and the shallow channels around Maui are where a lot of it ends up.

Humpbacks come into the shallow water between Maui, Lānaʻi, Molokaʻi and Kahoʻolawe to calve. Photo: Hawaii Tourism Authority (HTA)
All of that is from the Hawaiian Islands Humpback Whale National Marine Sanctuary, which is the authority worth reading before any operator's page.
The practical default, and the one that puts you closest to the channel.

Māʻalaea puts you closest to the channel, which is why so many boats leave from here. Photo: Hawaii Tourism Authority (HTA)
Convenient from South Maui and central to a large amount of boat inventory. It is the practical default if you are based in Kīhei or Wailea. Choose a West Maui departure only when it genuinely reduces your driving and the operator is strong — crossing the island for a harbor name is not worth it.
Convenient if you are already staying West, and a longer drive if you are not.
If you are staying West and a strong operator leaves from near you, take it. If you are not, the drive is rarely repaid.
In peak season you barely need a boat, and this is the cheapest whale watch on the island.
This is a supplement rather than a substitute. A boat gets you the scale and the sound; the shore gets you the surprise on an ordinary afternoon.
The vessel decides your comfort, not your odds.

Sailing off Maui. Photo: Hawaii Tourism Authority (HTA)
Neither vessel guarantees better whales. Pick the one your group will still be enjoying ninety minutes in.
Federal law sets the distance, and a boat that closes it is breaking the law rather than giving you a better trip.
In practice a good captain positions the boat, cuts the engine and lets the whales decide how close the encounter gets — which is also how the best encounters happen. The rules are published by the sanctuary.
Dedicated whale watch, November through April.
Private whale charter, for a group or a celebration.
Book a dedicated whale watch rather than hoping. A snorkel or sunset cruise that happens to see whales is not the same trip.
Book it early in your stay. Weather cancels boats and an early booking leaves room for a second attempt.
Bring a light layer and take the motion sickness seriously. Wind on the water feels cooler than it looks from the harbour.
Do not book a whale watch outside November through April. There is nothing dishonest about the boat, there are simply no whales.
Put binoculars in the car for the whole trip. In peak season the coast road does a lot of the work for free.
November through April, with the peak from January through March, per the Hawaiian Islands Humpback Whale National Marine Sanctuary.
Yes, in peak season, from the South and West Maui coasts. Binoculars matter more than elevation, and a boat still gives you the scale and the sound.
Māʻalaea for most people, and especially from Kīhei or Wailea. Take a West Maui departure only if you are staying West and the operator is strong.
A larger catamaran — stability, shade, bathrooms and easy boarding. Rafts are the wrong choice for young children.
No closer than 100 yards, by federal law, year-round and throughout Hawaiian waters. A captain who closes that distance is breaking the law.
No ethical wildlife experience is guaranteed. Inside the peak months the odds are very good, which is not the same as a promise.