The exact dates
Mexico's official whale watching season runs from December 8 to March 23. Those dates are not marketing — they are set by the federal environmental authority, and they are the window when licensed boats are allowed to approach whales in the bay.
The first whales usually show up in early December and the last stragglers leave by late March. If your trip falls outside that window, no operator in Puerto Vallarta can honestly promise you whales.
When you'll see the most
January and February are the peak. By then the bay is full: mothers with newborn calves in the shallow water near shore, and males competing in groups further out. That is when you see the behavior people come for — breaching, tail slapping, and the spray of a blow you can spot from a kilometer away.
December and March still work, but the count is lower and you may sail longer to find them. If your dates are flexible and whales are the reason you're coming, aim for the middle of the season.
Morning beats afternoon
Go in the morning. The bay is calmest before the afternoon wind picks up, which means a smoother ride and — more importantly — a flat surface where a blow or a fin is easy to spot. By 2 p.m. the chop hides everything.
Banderas Bay helps too: it is the largest bay in Mexico, over 42 km across and more than a kilometer deep in places, so the whales come well inside it. You are not crossing open ocean to find them.
Private boat or group tour?
A big group boat is cheaper per head and works fine. The trade-off is the schedule: it leaves when it leaves, returns when it returns, and if whales show up on the far side of the bay, forty other people have a say in whether you chase them.
On a private charter the boat is yours, so the captain follows the whales at your pace and you can stop for a swim or a snorkel afterwards. It also matters for photos — no one's head in your shot, and you can ask to reposition for the light.
By law, all boats keep a respectful distance and let the whales decide how close the encounter gets. That is the same on any boat. What changes is who else is standing next to you.
What to bring
Sunscreen, a hat, sunglasses and a light jacket — the wind on the water is colder than the beach. Bring a real camera if you have one; phones struggle with distance over water. And take motion sickness medication before you board if you're prone to it, not after.
