What Is AUM in Mutual Funds? Meaning, Calculation, Importance

When you start exploring mutual funds, one term appears almost everywhere—AUM. It’s usually shown as a big number, sometimes in crores, and often gives an impression of how “large” or “popular” a fund is. But what exactly does it mean, and should you rely on it while choosing a fund?

AUM is simple on the surface, but it carries deeper meaning when you understand how it works.

What Is AUM in Mutual Funds

What Is AUM?

AUM stands for Assets Under Management.

It represents the total market value of all the investments managed by a mutual fund scheme at a given time.

In simple words: AUM is the total money invested by all investors in a mutual fund.

How AUM Is Calculated

AUM is not just the total amount investors put in. It keeps changing based on market movements and investor activity.

Basic Calculation:

AUM = Total value of all securities + cash holdings – liabilities

In practical terms, it includes:

  • Value of stocks (equity funds)
  • Value of bonds (debt funds)
  • Cash and cash equivalents
  • Accrued income (like interest or dividends)

Since market prices change daily, AUM also changes every day.

Example to Understand AUM

Let’s say:

  • 1,000 investors invest ₹10,000 each
  • Total investment = ₹1 crore

If the market performs well and fund value grows to ₹1.2 crore → AUM becomes ₹1.2 crore

If investors withdraw money or markets fall → AUM decreases

So AUM is dynamic, not fixed.

Types of AUM

AUM can be looked at in different ways.

1. Scheme-Level AUM

  • Total assets of a specific mutual fund scheme

2. Fund House AUM

  • Total assets managed by an entire asset management company (AMC)

3. Category AUM

  • Total assets in a specific category (like equity, debt, hybrid funds)

What Affects AUM?

AUM changes due to multiple factors:

1. Market Performance

  • If stock prices rise → AUM increases
  • If market falls → AUM decreases

2. Investor Inflows

  • More people investing → AUM grows

3. Redemptions

  • Investors withdrawing money → AUM reduces

4. Fund Performance

  • Better returns attract more investors

Why AUM Is Important

AUM is more than just a number—it gives useful insights.

1. Indicates Fund Size

Large AUM means more money is being managed.

2. Reflects Investor Trust

Higher AUM often shows that many investors trust the fund.

3. Impacts Expense Ratio

Larger funds may have lower costs due to scale.

4. Shows Liquidity

Higher AUM usually means better ability to handle inflows and outflows.

High AUM vs Low AUM

Both have pros and cons. Bigger is not always better.

High AUM Funds

Advantages:

  • Stability and lower volatility
  • Better resources and research
  • Easier handling of large transactions

Disadvantages:

  • Harder to generate very high returns (especially in small-cap funds)
  • Less flexibility in investing

Low AUM Funds

Advantages:

  • More flexibility
  • Potential for higher returns in niche areas

Disadvantages:

  • Higher risk
  • Less stability
  • May face liquidity issues

AUM in Different Types of Funds

Equity Funds

  • Large AUM may limit flexibility in small-cap investing

Debt Funds

  • Higher AUM is generally positive (more stability)

Index Funds

  • Larger AUM improves tracking efficiency

AUM vs NAV – Don’t Confuse

These two are completely different.

AUM

  • Total size of the fund

NAV (Net Asset Value)

  • Price per unit of the fund

Example:

  • AUM = ₹1,000 crore
  • NAV = ₹100

👉 NAV tells unit price
👉 AUM tells total fund size

Does Higher AUM Mean Better Returns?

No, and this is a common myth.

  • A large fund does not guarantee high returns
  • A small fund is not always risky

Performance depends on:

  • Fund manager strategy
  • Market conditions
  • Asset allocation

AUM is just one factor, not the final decision-maker.

Role of AUM in Expense Ratio

Expense ratio is the fee charged by the fund.

  • Higher AUM → cost gets distributed → lower expense ratio
  • Lower AUM → higher cost per investor

This directly affects your returns.

How Investors Should Use AUM

AUM should be used as a supporting factor, not the main one.

Consider AUM Along With:

  • Past performance
  • Risk level
  • Fund manager track record
  • Investment objective

Common Mistakes to Avoid

Choosing Only Based on AUM

Big size doesn’t always mean better performance.

Ignoring Very Low AUM Funds

Some niche funds may perform well despite smaller size.

Not Checking Category Context

AUM should be compared within the same fund category.

AUM Trends – Why They Matter

Tracking AUM trends over time can give insights:

  • Rapid increase → growing popularity
  • Sudden drop → possible redemptions or poor performance

This helps you understand investor behavior.

Final Thoughts

AUM is a simple concept, but it carries meaningful signals about a mutual fund. It tells you how much money is being managed, how popular the fund is, and how stable it might be.

But it should never be your only deciding factor. A smart investor looks beyond size and focuses on overall performance, strategy, and long-term consistency.

In the end, AUM helps you understand the scale of a fund—but the real question is how well that money is being managed.