The best starting point is identifying how much waste your household generates and how frequent you have to empty your bins. The equation changes once you have recycling habits in place in your household. As the case may be in Singapore, majority of households are made up of high-rise flats with shared bin chutes, you can access your own need by the number of times that you empty your bins.
Landed properties are usually equipped with wheelie bins from your own estate, more often than not, 120 litre 2 wheel bins. Landed property owners will need to look at 2 matrix, essentially the size of the wheelie bin outside your gate and the number of times you have to empty your household bin.
According to NEA's Code of Practice (2015), the refuse output of a residential premise is approximately 20L per day. This number is used as a guide for waste collectors to estimate the frequency of waste collection. That typically sets your baseline to a 20L bin for a household consisting of 3 members on average. You also have to take note of the kind of household activity that you have everyday.
If you have doubt about the size of your bin that you should get, we recommend to go for the bigger ones. You will be surprised at how quickly it fills up!