Supplement dated August 1, 2025
to the Prospectus and Summary Prospectuses of each of the following funds (each, a Fund, and collectively, the Funds):
Fund
Prospectus and Summary Prospectus Dated
Columbia Funds Series Trust
 Columbia Capital Allocation Moderate Aggressive Portfolio
06/01/2025
 Columbia Capital Allocation Moderate Conservative Portfolio
06/01/2025
Columbia Funds Series Trust II
 Columbia Capital Allocation Aggressive Portfolio
06/01/2025
 Columbia Capital Allocation Conservative Portfolio
06/01/2025
 Columbia Capital Allocation Moderate Portfolio
06/01/2025
Effective immediately, the following changes are hereby made to each Fund's Prospectus and each Fund's Summary Prospectus. 
For Columbia Capital Allocation Conservative Portfolio
The information under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby revised to add the following:
On August 1, 2025, the Fund altered the composition of its Blended Benchmark. The New Blended Benchmark is designed to simplify the Blended Benchmark and provide a more appropriate Fund performance comparison than the Former Blended Benchmark. The returns of the Former Blended Benchmark will be shown for a one-year transition period.
The "Average Annual Total Returns" table under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby superseded and replaced with the following:
Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2024)
 
Share Class
Inception Date
1 Year
5 Years
10 Years
Class A
03/04/2004
 
 
 
returns before taxes
 
0.27%
1.01%
2.29%
returns after taxes on distributions
 
-1.01%
-0.36%
1.05%
returns after taxes on distributions and sale of Fund shares
 
0.20%
0.37%
1.37%
Class C returns before taxes
03/04/2004
3.66%
1.27%
2.03%
Class Inst returns before taxes
09/27/2010
5.57%
2.26%
3.04%
New Blended Benchmark (75% Bloomberg U.S. Aggregate Bond Index, 20%
Russell 3000® Index, 5% MSCI EAFE + Emerging Markets Index (Net)) (reflects
reinvested dividends net of withholding taxes on the MSCI EAFE + Emerging
Markets Index portion of the Blended Benchmark, and for all indexes reflects no
deductions for fees, expenses or other taxes)
 
5.70%
2.82%
3.88%
Bloomberg U.S. Aggregate Bond Index (reflects no deductions for fees,
expenses or taxes)
 
1.25%
-0.33%
1.35%
Russell 3000® Index (reflects no deductions for fees, expenses or taxes)
 
23.81%
13.86%
12.55%
Former Blended Benchmark (66% Bloomberg U.S. Aggregate Bond Index, 15%
Russell 3000® Index, 10% FTSE Three-Month U.S. Treasury Bill Index, 5% MSCI
EAFE Index (Net), 4% Bloomberg U.S. Corporate High-Yield Index) (reflects
reinvested dividends net of withholding taxes on the MSCI EAFE Index portion of
the Blended Benchmark, and for all indexes reflects no deductions for fees,
expenses or other taxes)
 
5.28%
2.65%
3.54%
For Columbia Capital Allocation Moderate Conservative Portfolio
The information under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby revised to add the following:
On August 1, 2025, the Fund altered the composition of its Blended Benchmark. The New Blended Benchmark is designed to simplify the Blended Benchmark and provide a more appropriate Fund performance comparison than the Former Blended Benchmark. The returns of the Former Blended Benchmark will be shown for a one-year transition period.
SUP000_00_175_(08/25)

The "Average Annual Total Returns" table under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby superseded and replaced with the following:
Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2024)
 
Share Class
Inception Date
1 Year
5 Years
10 Years
Class A
10/15/1996
 
 
 
returns before taxes
 
1.62%
2.47%
3.60%
returns after taxes on distributions
 
0.52%
0.81%
2.03%
returns after taxes on distributions and sale of Fund shares
 
1.05%
1.47%
2.35%
Class C returns before taxes
10/15/1996
5.96%
2.89%
3.43%
Class Inst returns before taxes
10/15/1996
8.06%
3.93%
4.47%
Class R returns before taxes
01/23/2006
7.56%
3.43%
3.96%
New Blended Benchmark (60% Bloomberg U.S. Aggregate Bond Index, 30%
Russell 3000® Index, 10% MSCI EAFE + Emerging Markets Index (Net))
(reflects reinvested dividends net of withholding taxes on the MSCI EAFE +
Emerging Markets Index portion of the Blended Benchmark, and for all indexes
reflects no deductions for fees, expenses or other taxes)
 
8.07%
4.49%
5.21%
Bloomberg U.S. Aggregate Bond Index (reflects no deductions for fees,
expenses or taxes)
 
1.25%
-0.33%
1.35%
Russell 3000® Index (reflects no deductions for fees, expenses or taxes)
 
23.81%
13.86%
12.55%
Former Blended Benchmark (consisting of 55.5% Bloomberg U.S. Aggregate
Bond Index, 26% Russell 3000® Index, 9% MSCI EAFE Index (Net), 5% FTSE
Three-Month U.S. Treasury Bill Index and 4.5% Bloomberg U.S. Corporate High-
Yield Index) (reflects reinvested dividends net of withholding taxes on the MSCI
EAFE Index portion of the Blended Benchmark, and for all indexes reflects no
deductions for fees, expenses or other taxes)
 
7.60%
4.33%
4.96%
For Columbia Capital Allocation Moderate Portfolio
The information under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby revised to add the following:
On August 1, 2025, the Fund altered the composition of its Blended Benchmark. The New Blended Benchmark is designed to simplify the Blended Benchmark and provide a more appropriate Fund performance comparison than the Former Blended Benchmark. The returns of the Former Blended Benchmark will be shown for a one-year transition period.
The "Average Annual Total Returns" table under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby superseded and replaced with the following:
Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2024)
 
Share Class
Inception Date
1 Year
5 Years
10 Years
Class A
03/04/2004
 
 
 
returns before taxes
 
3.89%
3.91%
5.05%
returns after taxes on distributions
 
2.27%
1.96%
3.13%
returns after taxes on distributions and sale of Fund shares
 
2.82%
2.56%
3.43%
Class C returns before taxes
03/04/2004
8.45%
4.37%
4.87%
Class Inst returns before taxes
09/27/2010
10.55%
5.42%
5.93%
Class Inst3 returns before taxes
06/13/2013
10.59%
5.49%
6.02%
New Blended Benchmark (45% Bloomberg U.S. Aggregate Bond Index, 40%
Russell 3000® Index, 15% MSCI EAFE + Emerging Markets Index (Net))
(reflects reinvested dividends net of withholding taxes on the MSCI EAFE +
Emerging Markets Index portion of the Blended Benchmark, and for all indexes
reflects no deductions for fees, expenses or other taxes)
 
10.49%
6.12%
6.51%
Russell 3000® Index (reflects no deductions for fees, expenses or taxes)
 
23.81%
13.86%
12.55%
2
SUP000_00_175_(08/25)

 
Share Class
Inception Date
1 Year
5 Years
10 Years
Bloomberg U.S. Aggregate Bond Index (reflects no deductions for fees,
expenses or taxes)
 
1.25%
-0.33%
1.35%
Former Blended Benchmark (consisting of 42.5% Bloomberg U.S. Aggregate
Bond Index, 37% Russell 3000® Index, 11% MSCI EAFE Index (Net), 7.5%
Bloomberg U.S. Corporate High-Yield Index and 2% MSCI Emerging Markets
Index (Net)) (reflects reinvested dividends net of withholding taxes on the MSCI
EAFE Index and the MSCI Emerging Markets Index portion of the Blended
Benchmark, and for all indexes reflects no deductions for fees, expenses or other
taxes)
 
10.22%
6.03%
6.43%
For Columbia Capital Allocation Moderate Aggressive Portfolio
The information under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby revised to add the following:
On August 1, 2025, the Fund altered the composition of its Blended Benchmark. The New Blended Benchmark is designed to simplify the Blended Benchmark and provide a more appropriate Fund performance comparison than the Former Blended Benchmark. The returns of the Former Blended Benchmark will be shown for a one-year transition period.
The "Average Annual Total Returns" table under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby superseded and replaced with the following:
Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2024)
 
Share Class
Inception Date
1 Year
5 Years
10 Years
Class A
10/15/1996
 
 
 
returns before taxes
 
6.52%
5.47%
6.31%
returns after taxes on distributions
 
4.71%
3.39%
4.25%
returns after taxes on distributions and sale of Fund shares
 
4.75%
3.84%
4.46%
Class C returns before taxes
10/15/1996
11.12%
5.94%
6.14%
Class Inst returns before taxes
10/15/1996
13.32%
7.00%
7.21%
Class Inst3 returns before taxes
06/13/2013
13.33%
7.09%
7.31%
Class R returns before taxes
01/23/2006
12.73%
6.46%
6.68%
Class S returns before taxes
10/02/2024
13.07%
6.74%
6.95%
New Blended Benchmark (50% Russell 3000® Index, 35% Bloomberg U.S.
Aggregate Bond Index, 15% MSCI EAFE + Emerging Markets Index (Net))
(reflects reinvested dividends net of withholding taxes on the MSCI EAFE +
Emerging Markets Index portion of the Blended Benchmark, and for all indexes
reflects no deductions for fees, expenses or other taxes)
 
12.74%
7.53%
7.62%
Russell 3000® Index (reflects no deductions for fees, expenses or taxes)
 
23.81%
13.86%
12.55%
Bloomberg U.S. Aggregate Bond Index (reflects no deductions for fees,
expenses or taxes)
 
1.25%
-0.33%
1.35%
Former Blended Benchmark (consisting of 49% Russell 3000® Index, 28.5%
Bloomberg U.S. Aggregate Bond Index, 12% MSCI EAFE Index (Net), 6.5%
Bloomberg U.S. Corporate High-Yield Index and 4% MSCI Emerging Markets
Index (Net)) (reflects reinvested dividends net of withholding taxes on the MSCI
EAFE Index and the MSCI Emerging Markets Index portion of the Blended
Benchmark, and for all indexes reflects no deductions for fees, expenses or other
taxes)
 
13.02%
7.77%
7.81%
For Columbia Capital Allocation Aggressive Portfolio
The information under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby revised to add the following:
On August 1, 2025, the Fund altered the composition of its Blended Benchmark. The New Blended Benchmark is designed to simplify the Blended Benchmark and provide a more appropriate Fund performance comparison than the Former Blended Benchmark. The returns of the Former Blended Benchmark will be shown for a one-year transition period.
3
SUP000_00_175_(08/25)

The "Average Annual Total Returns" table under the subsection "Performance Information" in the Summary Prospectus and in the "Summary of the Fund - Performance Information" section of the Prospectus is hereby superseded and replaced with the following:
Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2024)
 
Share Class
Inception Date
1 Year
5 Years
10 Years
Class A
03/04/2004
 
 
 
returns before taxes
 
8.81%
6.99%
7.46%
returns after taxes on distributions
 
7.46%
5.00%
5.31%
returns after taxes on distributions and sale of Fund shares
 
6.07%
5.08%
5.31%
Class C returns before taxes
03/04/2004
13.56%
7.44%
7.29%
Class Inst returns before taxes
09/27/2010
15.73%
8.52%
8.37%
Class Inst3 returns before taxes
06/13/2013
15.81%
8.60%
8.46%
Class R returns before taxes
09/27/2010
15.18%
7.99%
7.83%
New Blended Benchmark (60% Russell 3000® Index, 20% Bloomberg U.S.
Aggregate Bond Index, 20% MSCI EAFE + Emerging Markets Index (Net))
(reflects reinvested dividends net of withholding taxes on the MSCI EAFE +
Emerging Markets Index portion of the Blended Benchmark, and for all indexes
reflects no deductions for fees, expenses or other taxes)
 
15.23%
9.12%
8.87%
Russell 3000® Index (reflects no deductions for fees, expenses or taxes)
 
23.81%
13.86%
12.55%
Bloomberg U.S. Aggregate Bond Index (reflects no deductions for fees,
expenses or taxes)
 
1.25%
-0.33%
1.35%
Former Blended Benchmark (consisting of 60% Russell 3000® Index, 15%
Bloomberg U.S. Aggregate Bond Index, 14% MSCI EAFE Index (Net), 6% MSCI
Emerging Markets Index (Net) and 5% Bloomberg U.S. Corporate High-Yield
Index) (reflects reinvested dividends net of withholding taxes on the MSCI EAFE
Index and the MSCI Emerging Markets Index portion of the Blended Benchmark,
and for all indexes reflects no deductions for fees, expenses or other taxes)
 
15.63%
9.37%
9.08%
Shareholders should retain this Supplement for future reference.
4
SUP000_00_175_(08/25)