In general, when looking for the cheapest flight to Santiago, try to choose a flight departing in November for the best deal.
From most locations, booking your flights to Santiago around 44 days prior to your departure date finds the best deals.
From most locations, the cheapest day to fly to Santiago is Tuesday. Most users found that departing on a Saturday was most expensive.
On average you can find the best deals on plane tickets to Santiago when looking for flights with morning departure times.