Los Arcos Tours from Puerto Vallarta

Humpback whales are in Banderas Bay through the northern winter, roughly from the middle of December to the end of March, and the middle of that stretch is the most reliable. Outside those months the tours do not run at all. They are wild animals in a protected area, so no operator can guarantee a sighting — and one that does is telling you something it cannot keep.

They are different holidays, and this one is honest about what it lacks: there are no cenotes here and no Maya ruins, so if archaeology is the point of your trip, the Yucatán is the right coast. What Puerto Vallarta has instead is a real town you can walk, mountains that start behind it, and a bay deep enough for whales in winter.

Only on a tour with a licensed operator. The islands are a national park off Punta de Mita, the number of visitors allowed onto Playa del Amor each day is capped, and there are days the beach is closed entirely. Both the cap and the closed days are set by the park authority and have changed before, so have your operator confirm the current rules for your date.

Mid-August to mid-October is the hardest stretch: it is the hottest and wettest part of the year, afternoon thunderstorms are close to daily, humidity sits high, and the rivers push sediment into the bay so snorkelling visibility drops. Boats still run between storms and prices are at their lowest, but it is the honest answer to "when is it worst".

Not for the town or for the tours — almost everything picks up, and the Malecón and Zona Romántica are walkable. A car earns its keep if you want Sayulita, San Pancho or San Sebastián del Oeste on your own schedule. Note that Mexican liability insurance is required and is not part of the headline rental price, so compare the total rather than the daily rate.

From December to March the boats fill up, and whale trips and the Marietas can sell out days ahead — over Christmas, New Year and Semana Santa longer than that. Outside high season a day or two is usually enough. Since most tours cancel free up to 24 hours before, booking early costs nothing but a decision.