If you want a cheap flight from Hong Kong to Singapore, you've got 13 airlines to choose from. You can use the search box to filter your preferences, but we've found that the cheapest day to fly is 23 / Jan / 2020.
Singapore Changi International Airport is just one of the airports in Singapore. If you're not set on a specific airport, try changing your search from Singapore Changi International Airport to Singapore to see a broader range of flights – they might be cheaper. It usually takes about 9 hrs 50 mins to fly 2567 km to Singapore Changi International Airport.
If you're planning on going to Singapore during this time, you could take a look at other airport options. Or you could try to get a last-minute bargain.