"It must also be noted that there is a cap. to your Medisave Contribution (which is up to $49,800 as of 2016) and Special Account (which is up to S$166,000 as of 2018)." May I ask what this means?

Does it make any diffferent if i topup my SA at Jan or at Dec the same year?​​​

Hi anon,

This means that, as of 2016, you could not have more than $49.8K in your MA. This is the absolute ceiling and is known as the Basic Healthcare Sum or BHS. The figure for this ceiling is now $60K and will be $63K in 2021. Any contributions in excess of the BHS spills over to SA (if SA is not at FRS) or OA.

As for SA, you could not do voluntary contributions once you have $166K in your SA (as of 2016). Mandatory contributions from work will still cause your SA to increase however. The figure is now $181K for 2020. This is known as the full retirement sum or FRS.