Most buses from Santiago leave in the afternoon/evening and arrive in Puerto Montt/Varas the following morning.
Duration: The trip lasts approximately 12 hours.
Prices: To see prices, go to recorrido.cl. Prices vary depending on the type of service and dates of travel. In the high season and holidays prices are generally higher.
https://goo.gl/maps/UH2eWjVDbryDf3y3A
Horarios: Buses from Santiago. Buses from Santiago leave in the afternoon/evening and arrive the next day.
Below are details of some of the companies that operate the Santiago - Puerto Montt/Puerto Varas route:
Check out the website Puerto Montt / Puerto Varas to Cochamó.