What should I do to reduce my payable income tax?

I'm will be having a taxable income of 108k (after eligible relief and have not added in bonus as it is still unknown).

This means I will need to reduce the taxable income by 28k to reach the previous tier of 7%. I've included all my tax relief that I'm eligible for (CPF, NS, donation etc).

What I can do is top up 15k to SRS, or donate more for the 250% tax relief, or CPF top-up. Please advise what is the best option. Thanks in advance.

Assuming that you choose to top up to SRS, do ensure that you do not stop there. In fact, make your money work harder for you by parking it into various tools, e.g. annuity.

If you top up to your Special Account, the same amount will be deducted from your taxable income of 108k, up to $7k. Additionally, you may choose to top-up to your parents or grandparents’ Special Account or Retirement account for the same purpose.

Next, you can top-up your CPF MediSave account up to the Basic Healthcare sum. Either option, do note that this is irreversible.

On top of that, you may consider signing up for courses and claim for course fee relief. If you are a self-employed, or have expenses that are incurred in order to earn your income, you can declare these business expenses too.

If you have some spare cash left and do not mind doing a bit of charity, charitable giving is definitely one of the fastest option to reduce your taxable income.