Generally, if you are paying your premiums monthly instead of annually, you can expect to pay around 2% more in total premiums, which is quite small. This is not the same as income tax whereby opting to spread your premiums over 12 months will result in the same total amount paid as compared to paying in one lump sum.
For some, this difference between yearly and monthly premiums may not be a lot, and it may actually aid them in their cash flow month to month. So you will have to see your own circumstances and ability to generate returns on the unpaid premiums in excess of the extra premiums that you have to pay (due to paying via monthly mode), in order to decide.
For insurance premium, it depends on the type of policy and whether there is a modal factor.
For policies that make no difference paying monthly or annually, then pay it monthly if you need the liquidity. Otherwise, just do it annually to keep things simple. This is because we may face other issues, e.g. unsuccessful GIRO deduction and the policy lapse. Consequently, this gives us more problems than mere interest.
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