Bank Deposits vs Inflation – Are Your Savings Really Earning?

Bank deposits have been Poles' favourite way of saving for decades. They are simple, safe, and require no financial expertise. But there is one fundamental question that too few savers ask: is my deposit really earning, or does it only create the illusion of profit while inflation eats away at my money? In this article, we answer that question by analysing historical data, market mechanisms, and real alternatives.

How Do Bank Deposits Work?

A bank deposit is an agreement under which you place money in a bank for a specified period in return for an agreed interest rate. At the end of the term, the bank returns your deposited amount plus interest (minus capital gains tax – 19%).

Types of Deposits

Fixed-term deposits – classic deposits for 1, 3, 6, 12 or more months with a fixed interest rate. They usually offer the highest rates, but money is locked for the duration.

Renewable deposits – automatically renewed for another period upon expiry. Convenient, but the renewal rate may differ from the original.

Progressive deposits – the interest rate increases with each period. They encourage longer saving.

Structured deposits – returns depend on the performance of a specific index or asset. More complex, but potentially higher returns.

Promotional deposits – offered to new customers or under special conditions. Often higher interest rates, but for short periods and with amount limits.

Deposit Interest vs Inflation – History in Poland

To understand the relationship between deposits and inflation, it is worth looking at historical data.

2015–2019: The Low-Rate Era

During the period of low NBP interest rates (reference rate 1.5%), deposit rates were typically 1.5–3% annually. Inflation ranged from -1% (deflation) to 2.5%. In this period, deposits generally covered inflation or even gave a small real return.

Real deposit return: from -0.5% to +2% (before tax)

2020–2021: Pandemic and Rate Cuts

NBP cut interest rates to near zero (0.1%). Deposit rates fell to 0.01–0.5%, while inflation began to rise (3–8%).

Real deposit return: from -3% to -7%

2022–2023: The Inflation Shock

Inflation exploded (10–18%), and despite NBP rate hikes (to 6.75%), deposit rates could not keep up – typically 5–8%.

Real deposit return: from -5% to -12%

This was the worst period for deposit holders in decades. Someone holding PLN 100,000 on a deposit earning 7%, with inflation at 17%, was losing roughly PLN 10,000 per year in real terms.

2024–2026: Normalisation

As inflation fell towards the NBP target, deposits began offering more attractive real returns. With inflation at 3–5% and deposit rates of 4–6%, the real return hovers around zero or is slightly negative (after accounting for tax).

Why Do Deposits Almost Never Beat Inflation?

There are several structural reasons why deposit rates systematically fail to keep pace with inflation:

1. Bank Margin

Banks earn on the difference between the rate they pay depositors and the rate they charge borrowers. This margin means deposit rates are always lower than market rates.

2. Delayed Adjustment

When inflation rises, banks do not raise deposit rates immediately. The process is delayed and often disproportionate – banks are quicker to raise lending rates than deposit rates.

3. Belka Tax (19%)

The bank withholds 19% capital gains tax from deposit interest. This means the effective rate is nearly one-fifth lower than the nominal rate. If a deposit offers 6%, after tax you are left with 4.86%.

4. Information Asymmetry

Banks have no incentive to inform customers that their deposits are not keeping up with inflation. On the contrary, they promote the nominal rate, which looks attractive.

5. Limited Competition

Although banks compete for deposits, price competition in the deposit segment is limited. All banks have access to the same money market and offer similar rates.

Real Rate of Return – How to Calculate It

The formula for the real rate of return on a deposit (after tax):

Real rate of return = nominal rate × (1 - 0.19) - CPI inflation

Example

12-month deposit, interest rate 6%, CPI inflation 4.5%:

• After-tax rate: 6% × 0.81 = 4.86%
• Real rate of return: 4.86% - 4.5% = +0.36%

In this case the deposit gives a marginal real gain. But if inflation rises to 5.5%, the real return drops to -0.64%.

When Does a Deposit Yield a Real Profit?

A deposit yields a real profit only when:

Nominal rate × 0.81 > CPI inflation

This means the nominal rate must exceed inflation by at least 23.5% (since 1/0.81 ≈ 1.235). At 5% inflation, the deposit would need to offer above 6.17% to produce a real gain.

Comparing Deposits with Alternatives

Deposits vs COI/EDO Bonds

Inflation-indexed bonds have a key advantage – their rate automatically adjusts to inflation plus a margin. A deposit at 6% with inflation at 10% gives a real loss, while COI with a 1.25% margin at 10% inflation yields 11.25%.

When deposits win: With very low or negative inflation, short horizons (under a year), need for immediate liquidity.

When bonds win: With high and variable inflation, horizons above one year, for medium- and long-term goals.

Deposits vs Savings Accounts

Savings accounts typically offer lower interest than deposits but full liquidity. For an emergency fund (3–6 months of expenses), a savings account is a better solution than a deposit.

Deposits vs Money Market Funds

Money market funds invest in short-term debt instruments and offer returns similar to deposits but with greater liquidity. Management fees reduce the return, but flexibility may compensate.

Strategies for Maximising Deposit Returns

If you still choose deposits, here is how to maximise returns:

1. Hunt for Promotions

Banks regularly offer promotional deposits with elevated rates. Follow financial comparison sites and be ready to move your money.

2. New Banks and Customers

The highest rates are offered to new customers. Some savers regularly transfer funds between banks to take advantage of promotions.

3. Deposit Ladder

Instead of one large deposit, spread your money across several deposits with different maturities. This way, a portion of your funds becomes available regularly, which you can reinvest at new rates.

4. Negotiate

For larger amounts (PLN 50,000+), banks are often willing to offer individually higher rates. Do not be afraid to ask.

5. Compare Effective Rates, Not Nominal Ones

The annualised rate (p.a.) can be misleading for shorter deposits. Compare the APR or calculate net returns yourself.

Deposits and the Psychology of Saving

The psychological role of deposits cannot be ignored. For many Poles, a deposit represents:

A Sense of Security

The Bank Guarantee Fund (BFG) guarantee up to the equivalent of EUR 100,000 per person per bank provides a real sense of safety. This is no illusion – money on a deposit is truly safe (nominally).

Simplicity

You do not need to understand financial markets, follow exchange rates, or make complex decisions. You deposit money, wait, and collect with interest.

Discipline

Locking money in a fixed-term deposit helps avoid impulsive spending. For people with financial self-discipline issues, this may matter more than an optimal rate of return.

Habit

Poles have been saving in deposits for generations. It is a habit that is hard to break, even when rational analysis points to better alternatives.

When Does a Deposit Make Sense?

Despite rarely beating inflation, there are situations where deposits make sense:

1. Emergency Fund

An emergency fund (3–6 months of expenses) should be easily accessible and safe. A short deposit or savings account is the right place.

2. Short-Term Savings Goal

If you need the money in 3–12 months (e.g. for a holiday, renovation), a deposit protects it from spending and gives at least a symbolic return.

3. Risk Aversion

If the stress of investing in financial markets is unbearable for you, a deposit is better than not saving at all.

4. Period of Uncertainty

When you lack clearly defined plans and need time to think through your investment strategy, a deposit is a good "parking spot" for money.

When Does a Deposit Not Make Sense?

1. Long-Term Saving (Over 2 Years)

With a horizon over 2 years, there are instruments with a much higher probability of beating inflation (indexed bonds, ETFs, real estate).

2. Large Amounts Without a Plan

Keeping PLN 200,000+ on a deposit for years is an almost certain real loss. Part of this money should work more effectively.

3. High Inflation

During periods of high inflation (above 5%), deposits practically guarantee a real loss. This is the time to look for alternatives.

How to Monitor Your Savings

The key to smart financial decisions is regular monitoring – not just of nominal account balances but above all of the real value of your savings. Freenance helps track how inflation affects your money and whether your chosen savings strategy is actually working.

What to Watch

• Real rate of return – the only metric that truly matters
• Comparison with alternatives – could you earn more at acceptable risk?
• Inflation trend – GUS data and NBP forecasts
• NBP interest rates – they affect deposit rates with a delay

Summary

Bank deposits are a safe, simple, and understandable savings instrument. But do not fool yourself – in most periods, they do not protect against inflation. Key takeaways:

1. Deposits rarely beat inflation after accounting for the Belka tax
2. The real rate of return on deposits is most often negative or close to zero
3. There are structural reasons why deposits fail to keep up with inflation
4. Deposits make sense as an emergency fund and short-term cash parking
5. For longer horizons, consider inflation-indexed bonds, ETFs, or other instruments
6. Diversification is key – deposits can be part of a portfolio, but not the entire portfolio

Do not be deceived by the illusion of nominal interest. What matters is the real value of your money – how much you can buy with it. And that value must be actively protected.