Vanguard Mega Cap Index Fund
Vanguard Mega Cap Value Index Fund
Supplement Dated July 29, 2026, to the Prospectus and Summary Prospectuses Dated December 19, 2025 (as supplemented on June 30, 2026)
Important Changes to the Funds
 
Morningstar, Inc. (“Morningstar”) has announced the acquisition of the Center for Research in Security Prices (“CRSP”) and its CRSP Market Indexes. As a result of these changes, the board of trustees of Vanguard World Fund has approved the renaming of Vanguard Mega Cap Index Fund and Vanguard Mega Cap Value Index Fund (each, a “Fund” and collectively, the “Funds”) as shown below.
The name changes are effective as of July 29, 2026. Each Fund’s investment objective, strategies, and polices remain unchanged.
 
Current Fund Name
New Fund Name
New Corresponding Name
for ETF Share Class
Vanguard Mega Cap Index
Fund
Vanguard Morningstar Mega
Cap Index Fund
Vanguard Morningstar Mega
Cap ETF
Vanguard Mega Cap Value
Index Fund
Vanguard Morningstar Mega
Cap Value Index Fund
Vanguard Morningstar Mega
Cap Value ETF
 
Morningstar’s acquisition of CRSP will also result in name changes of each Fund’s target index, as shown below. These changes are effective as of July 29, 2026. 
Current Fund Name
Current Target Index Name
New Target Index Name
Vanguard Mega Cap Index
Fund
CRSP US Mega Cap Index
Morningstar US Mega Cap
Index
Vanguard Mega Cap Value
Index Fund
CRSP US Mega Cap Value
Index
Morningstar US Mega Cap
Value Index
 
 
© 2026 The Vanguard Group, Inc. All rights reserved.
Vanguard Marketing Corporation, Distributor.
PSI 828A 072026

Vanguard World Fund

Supplement Dated July 29, 2026, to the Statements of Additional Information Dated December 19, 2025 (as restated on June 30, 2026)

Important Changes to Vanguard Mega Cap Index Fund and Vanguard Mega Cap Value Index Fund (each, a “Fund” and collectively, the “Funds”)

Morningstar, Inc. (“Morningstar”) has announced the acquisition of the Center for Research in Security Prices (“CRSP”) and its CRSP Market Indexes. As a result of these changes, the board of trustees of Vanguard World Fund has approved the renaming of each Fund, as shown below.

The name changes are effective as of July 29, 2026. Each Fund’s investment objective, strategies, and polices remain unchanged.

Current Fund Name

New Fund Name

New Corresponding Name for ETF Share

 

 

Class

Vanguard Mega Cap Index Fund

Vanguard Morningstar Mega Cap Index Fund

Vanguard Morningstar Mega Cap ETF

Vanguard Mega Cap Value Index Fund

Vanguard Morningstar Mega Cap Value

Vanguard Morningstar Mega Cap Value ETF

 

Index Fund

 

Morningstar’s acquisition of CRSP will also result in name changes of each Fund’s target index, as shown below. These changes are effective as of July 29, 2026.

Current Fund Name

Current Target Index Name

New Target Index Name

Vanguard Mega Cap Index Fund

CRSP US Mega Cap Index

Morningstar US Mega Cap Index

Vanguard Mega Cap Value Index Fund

CRSP US Mega Cap Value Index

Morningstar US Mega Cap Value Index

© 2026 The Vanguard Group, Inc. All rights reserved.

SAI 023A 072026

Vanguard Marketing Corporation, Distributor.