Fixed deposits remain a popular choice among investors who want predictable returns without taking direct exposure to market fluctuations. However, choosing an FD involves more than simply comparing interest rates. One important decision is whether you want the interest credited regularly or would prefer to leave it invested until maturity.

Banks generally offer both non-cumulative FDs, where interest can be paid periodically, and cumulative FDs, where the interest remains invested and compounds over the tenure.

Suppose you invest ₹5 lakh for five years at an annual interest rate of 7.1%. Would taking the interest every month be more beneficial, or could you earn more by waiting until maturity?

The difference can be significant because of the power of compounding.

Option 1: How Much Can a ₹5 Lakh FD Pay Every Month?

Consider a fixed deposit of ₹5 lakh carrying an annual interest rate of 7.1%.

If you choose the monthly interest payout option, the example in the source estimates that you could receive approximately ₹2,958 every month.

Over five years, the total interest payout would work out to around ₹1.77 lakh.

Your original ₹5 lakh principal remains invested throughout the FD tenure and is returned when the deposit matures.

So, broadly, the arrangement looks like this:

The biggest advantage is straightforward: you receive regular cash flow without withdrawing your principal.

However, there is a trade-off. Because the interest is paid out instead of remaining inside the FD, that money does not continue earning interest within the deposit.

Option 2: What Happens With a Cumulative FD?

Now consider investing the same ₹5 lakh at the same assumed 7.1% interest rate for five years but selecting the cumulative option.

In this case, you do not receive monthly interest payments.

Instead, the interest earned is added to the deposit, and subsequent interest is calculated on the increased amount. This creates the compounding effect, commonly described as earning interest on interest.

According to the calculation given in the source, ₹5 lakh could grow to approximately ₹7.11 lakh after five years.

That means the estimated interest earned would be about ₹2.11 lakh.

The calculation can be summarised as follows:

The investor gives up regular income during the five-year period but receives a larger amount at maturity.

Monthly Interest vs Cumulative FD: Which Gives More?

The comparison provided in the source is:

Based on these estimates, the cumulative FD generates roughly ₹33,000 more interest over five years.

The difference is primarily created by compounding.

With the monthly payout option, interest leaves the FD regularly. With the cumulative option, the interest stays invested and itself starts earning interest.

Why Does Compounding Make Such a Difference?

Compounding becomes increasingly powerful as the investment period gets longer.

Imagine that your FD earns interest during the first compounding period. Instead of withdrawing that interest, it is added to the principal.

During the next period, interest is calculated on both the original principal and previously accumulated interest.

The process keeps repeating.

As a result, the amount on which interest is calculated gradually increases.

That is why two FDs with the same starting amount, interest rate and tenure can ultimately generate different effective returns depending on how the interest is handled.

When Does a Monthly Interest FD Make Sense?

Higher maturity value is not necessarily the only objective for every investor.

Some people need a predictable income stream.

For example, retirees may want regular cash flow to meet household expenses. Someone who has received a lump sum but does not have a regular salary may also prefer periodic interest payments.

For such investors, a monthly payout FD can be useful because it provides recurring income while keeping the original principal invested.

The source similarly notes that monthly-interest FDs may suit investors who need regular income, particularly after retirement.

The investor is effectively choosing cash flow today instead of additional compounding later.

When Could a Cumulative FD Be Better?

A cumulative FD may be more suitable if you do not need regular income from the investment.

Suppose you are saving toward a future expense that is five years away. If you can leave both the principal and interest untouched throughout that period, compounding can help increase the final corpus.

This could make cumulative FDs more appropriate for goals where building a larger lump sum is more important than receiving monthly cash.

The source explains that leaving interest inside the FD allows interest to accumulate on previous interest, increasing the total amount over longer periods.

Don't Forget That Actual FD Calculations Can Differ

The ₹7.11 lakh figure is an illustrative calculation based on the assumptions used in the source. It should not be treated as a guaranteed maturity amount for every bank offering a 7.1% headline rate.

Actual returns can vary depending on factors such as the bank's compounding frequency, payout method, deposit terms and applicable interest-rate rules.

Monthly payout calculations can also differ from simply dividing the annual interest by 12 because banks may calculate periodic payouts according to their specific terms.

Therefore, investors should check the bank's official FD calculator or maturity illustration before opening a deposit.

Tax Can Change Your Effective Return

Another important factor is taxation.

Interest earned from a fixed deposit is generally taxable according to the investor's applicable income-tax rules. Depending on the amount of interest and applicable provisions, tax may also be deducted at source.

This means two investors putting the same amount into an identical FD could have different post-tax outcomes depending on their tax situations.

The source therefore advises investors to consider the post-tax return, rather than making a decision solely on the advertised interest rate.

Which FD Option Should You Choose?

There is no single option that is automatically best for everyone.

If your priority is regular monthly income, a non-cumulative FD with periodic interest payouts may be more practical.

If your goal is maximising the maturity corpus and you do not require income during the investment period, a cumulative FD may have the advantage because of compounding.

Using the source's ₹5 lakh, 7.1% and five-year illustration, the difference is clear: the monthly option generates approximately ₹1.77 lakh in total interest payments, while the cumulative option produces around ₹2.11 lakh in interest and a maturity corpus of approximately ₹7.11 lakh.

That works out to roughly ₹33,000 of additional interest from the cumulative option in this example.

The final decision, however, should be based not merely on which number is larger but on whether you need income now or a bigger lump sum later.

Disclaimer: This article is for general information and educational purposes only. Actual FD returns, maturity values, taxation and payout calculations depend on the bank's terms and applicable tax rules. Check the deposit conditions and consider professional advice before making financial decisions.