Assets Under Management (AUM): What Asset Managers Actually Manage

Assets under management (AUM) is the value of client assets that an investment manager includes in its managed-asset population under the firm's stated methodology.

AUM is an operating scale measure. It is not the asset manager's own balance-sheet assets, and it is not revenue.

That distinction sounds basic, but it changes how investors should read an asset manager's growth. A firm can add hundreds of billions of dollars of AUM while recognizing only a small fraction of that amount as fees.

The AUM bridge matters more than the ending number

A useful way to analyze AUM is as a rollforward:

1Beginning AUM
2+ Net client flows
3+ Market appreciation or depreciation
4+ Foreign-exchange effects
5+ Acquisitions or other scope changes
6= Ending AUM

Suppose a manager begins the quarter with $1.0 trillion of AUM, receives $20 billion of net inflows, benefits from $70 billion of market appreciation, and loses $10 billion from currency translation:

1$1.00T
2+ $0.02T flows
3+ $0.07T markets
4- $0.01T FX
5= $1.08T ending AUM

Ending AUM grew 8%, but only 2 percentage points of the beginning balance came from net client flows. The rest came from markets and currency.

That is a materially different growth story from a manager that reaches the same ending AUM through client wins.

AUM can rise while clients withdraw money

This is one of the most important asset-management distinctions.

T. Rowe Price ended the second quarter of 2026 with about $1.89 trillion of AUM even though it reported $6.5 billion of quarterly net client outflows. Market appreciation more than offset those withdrawals.

BlackRock's filings similarly separate net inflows, market appreciation, foreign-exchange effects, and transaction-related additions when explaining changes in AUM.

A rising stock market can therefore hide weak organic flows. A falling market can also obscure strong client demand.

Total AUM is not necessarily fee-earning AUM

Not every dollar included in total AUM generates the same management-fee economics.

Alternative managers often report a narrower fee-earning or fee-generating AUM measure. Blackstone, for example, separately reports total AUM and fee-earning AUM. Apollo similarly reports total AUM and fee-generating AUM.

The gap can reflect assets that have not yet begun paying fees, assets that pay only performance-related economics, committed but not fully fee-bearing capital, or other contractual differences.

For revenue analysis, total AUM is therefore the starting point rather than the final answer.

AUM definitions differ across managers

AUM is not one perfectly standardized accounting line.

Managers can differ in how they treat:

• leverage;
• committed but uninvested capital;
• model-delivery assets;
• subadvised assets;
• advisory versus discretionary mandates;
• fund-of-funds duplication;
• private-market realizations;
• joint ventures and strategic partnerships; and
• assets added through acquisitions.

Apollo explicitly warns that its AUM calculation may differ from other investment managers and from regulatory AUM reported on forms such as Form ADV.

That is why a cross-company AUM comparison should begin with methodology, not just the headline number.

AUM growth and revenue growth can diverge

Asset-management revenue depends on the assets that actually generate fees and on the fee rates attached to those assets.

A rough bridge is:

1Management-fee revenue
2≈ Average fee-earning assets × Effective fee rate

If AUM growth is concentrated in low-fee index products, revenue may grow more slowly than AUM. If the mix shifts toward higher-fee private markets or specialized active strategies, revenue can grow faster.

Performance fees can add another layer that is not captured by a simple AUM-times-fee-rate model.

Current filing examples

BlackRock reported $15.3 trillion of AUM at June 30, 2026 and explained the year-over-year increase through market appreciation, net inflows, transaction-related additions, and foreign-exchange effects. T. Rowe Price reported $1.893 trillion of ending AUM for the same date and separately disclosed its net client flows and market appreciation.

Sources:

• BlackRock Q2 2026 Form 10-Q
• BlackRock Q2 2026 earnings supplement
• T. Rowe Price Q2 2026 Form 10-Q
• T. Rowe Price Q2 2026 earnings release

AUM is most useful when you can explain how it changed, which portion earns fees, and what fee economics attach to that asset mix. The headline total by itself cannot answer those questions.

Explore more topics in the Financial Research Encyclopedia.