In general, when booking your flight to Penang, October is the cheapest month on average.
From most locations, booking your flights to Penang around 60 days prior to your departure date finds the best deals.
From most locations, the cheapest day to fly to Penang is Wednesday. Most users found that departing on a Saturday was most expensive.
On average you can find the best deals on plane tickets to Penang when looking for flights with midday departure times.