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Investments in Debt and Equity Securities (Tables) | 9 Months Ended
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Sep. 30, 2025
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 172 |  |  | $ | — |  |  | $ | — |  |  | $ | 139 |
Equity securities | 5,938 |  |  | 17 |  |  | 8,435 |  |  | 5,753 |  |  | 61 |  |  | 8,233 |
Corporate debt securities | 21 |  |  | 19 |  |  | 1,021 |  |  | 6 |  |  | 33 |  |  | 673 |
Municipal bonds | 4 |  |  | 15 |  |  | 374 |  |  | 2 |  |  | 14 |  |  | 342 |
U.S. government bonds | 32 |  |  | 43 |  |  | 2,488 |  |  | 3 |  |  | 84 |  |  | 1,806 |
Other debt securities | 3 |  |  | 5 |  |  | 287 |  |  | 1 |  |  | 8 |  |  | 239 |
Total NDTF Investments | $ | 5,998 |  |  | $ | 99 |  |  | $ | 12,777 |  |  | $ | 5,765 |  |  | $ | 200 |  |  | $ | 11,432 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 76 |  |  | $ | — |  |  | $ | — |  |  | $ | 47 |
Equity securities | 54 |  |  | — |  |  | 134 |  |  | 39 |  |  | 4 |  |  | 160 |
Corporate debt securities | — |  |  | 2 |  |  | 70 |  |  | — |  |  | 5 |  |  | 79 |
Municipal bonds | — |  |  | 2 |  |  | 69 |  |  | — |  |  | 1 |  |  | 83 |
U.S. government bonds | — |  |  | 4 |  |  | 56 |  |  | — |  |  | 5 |  |  | 59 |
Other debt securities | — |  |  | 2 |  |  | 49 |  |  | — |  |  | 4 |  |  | 45 |
Total Other Investments | $ | 54 |  |  | $ | 10 |  |  | $ | 454 |  |  | $ | 39 |  |  | $ | 19 |  |  | $ | 473 |
Total Investments | $ | 6,052 |  |  | $ | 109 |  |  | $ | 13,231 |  |  | $ | 5,804 |  |  | $ | 219 |  |  | $ | 11,905 |
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 172 |  |  | $ | — |  |  | $ | — |  |  | $ | 139 |
Equity securities | 5,938 |  |  | 17 |  |  | 8,435 |  |  | 5,753 |  |  | 61 |  |  | 8,233 |
Corporate debt securities | 21 |  |  | 19 |  |  | 1,021 |  |  | 6 |  |  | 33 |  |  | 673 |
Municipal bonds | 4 |  |  | 15 |  |  | 374 |  |  | 2 |  |  | 14 |  |  | 342 |
U.S. government bonds | 32 |  |  | 43 |  |  | 2,488 |  |  | 3 |  |  | 84 |  |  | 1,806 |
Other debt securities | 3 |  |  | 5 |  |  | 287 |  |  | 1 |  |  | 8 |  |  | 239 |
Total NDTF Investments | $ | 5,998 |  |  | $ | 99 |  |  | $ | 12,777 |  |  | $ | 5,765 |  |  | $ | 200 |  |  | $ | 11,432 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 76 |  |  | $ | — |  |  | $ | — |  |  | $ | 47 |
Equity securities | 54 |  |  | — |  |  | 134 |  |  | 39 |  |  | 4 |  |  | 160 |
Corporate debt securities | — |  |  | 2 |  |  | 70 |  |  | — |  |  | 5 |  |  | 79 |
Municipal bonds | — |  |  | 2 |  |  | 69 |  |  | — |  |  | 1 |  |  | 83 |
U.S. government bonds | — |  |  | 4 |  |  | 56 |  |  | — |  |  | 5 |  |  | 59 |
Other debt securities | — |  |  | 2 |  |  | 49 |  |  | — |  |  | 4 |  |  | 45 |
Total Other Investments | $ | 54 |  |  | $ | 10 |  |  | $ | 454 |  |  | $ | 39 |  |  | $ | 19 |  |  | $ | 473 |
Total Investments | $ | 6,052 |  |  | $ | 109 |  |  | $ | 13,231 |  |  | $ | 5,804 |  |  | $ | 219 |  |  | $ | 11,905 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2025, and 2024, were as follows.
| Three Months Ended |  | Nine Months Ended
(in millions) | September 30, 2025 |  | September 30, 2024 |  | September 30, 2025 |  | September 30, 2024
FV-NI: |  |  |  |  |  |  |
Realized gains | $ | 848 |  |  | $ | 61 |  |  | $ | 1,015 |  |  | $ | 256 |
Realized losses | 21 |  |  | 19 |  |  | 102 |  |  | 64 |
AFS: |  |  |  |  |  |  |
Realized gains | 23 |  |  | 10 |  |  | 43 |  |  | 22 |
Realized losses | 20 |  |  | 8 |  |  | 57 |  |  | 44 |
Investments Classified by Contractual Maturity Date | The table below summarizes the maturity date for debt securities.
| September 30, 2025
|  |  | Duke |  |  |  | Duke |  | Duke |  | Duke
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Indiana
Due in one year or less | $ | 92 |  |  | $ | 9 |  |  | $ | 82 |  |  | $ | 10 |  |  | $ | 72 |  |  | $ | 1 |
Due after one through five years | 1,138 |  |  | 571 |  |  | 507 |  |  | 464 |  |  | 43 |  |  | 8 |
Due after five through 10 years | 900 |  |  | 460 |  |  | 394 |  |  | 377 |  |  | 17 |  |  | 6 |
Due after 10 years | 2,284 |  |  | 1,289 |  |  | 882 |  |  | 834 |  |  | 48 |  |  | 13 |
Total | $ | 4,414 |  |  | $ | 2,329 |  |  | $ | 1,865 |  |  | $ | 1,685 |  |  | $ | 180 |  |  | $ | 28 |
Duke Energy Carolinas |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 84 |  |  | $ | — |  |  | $ | — |  |  | $ | 62 |
Equity securities | 3,483 |  |  | 11 |  |  | 4,856 |  |  | 3,386 |  |  | 33 |  |  | 4,751 |
Corporate debt securities | 11 |  |  | 16 |  |  | 637 |  |  | 2 |  |  | 27 |  |  | 401 |
Municipal bonds | — |  |  | 5 |  |  | 50 |  |  | — |  |  | 4 |  |  | 36 |
U.S. government bonds | 17 |  |  | 28 |  |  | 1,397 |  |  | — |  |  | 50 |  |  | 991 |
Other debt securities | 3 |  |  | 5 |  |  | 245 |  |  | 1 |  |  | 8 |  |  | 223 |
Total NDTF Investments | $ | 3,514 |  |  | $ | 65 |  |  | $ | 7,269 |  |  | $ | 3,389 |  |  | $ | 122 |  |  | $ | 6,464 |
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 84 |  |  | $ | — |  |  | $ | — |  |  | $ | 62 |
Equity securities | 3,483 |  |  | 11 |  |  | 4,856 |  |  | 3,386 |  |  | 33 |  |  | 4,751 |
Corporate debt securities | 11 |  |  | 16 |  |  | 637 |  |  | 2 |  |  | 27 |  |  | 401 |
Municipal bonds | — |  |  | 5 |  |  | 50 |  |  | — |  |  | 4 |  |  | 36 |
U.S. government bonds | 17 |  |  | 28 |  |  | 1,397 |  |  | — |  |  | 50 |  |  | 991 |
Other debt securities | 3 |  |  | 5 |  |  | 245 |  |  | 1 |  |  | 8 |  |  | 223 |
Total NDTF Investments | $ | 3,514 |  |  | $ | 65 |  |  | $ | 7,269 |  |  | $ | 3,389 |  |  | $ | 122 |  |  | $ | 6,464 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2025, and 2024, were as follows.
| Three Months Ended |  | Nine Months Ended
(in millions) | September 30, 2025 |  | September 30, 2024 |  | September 30, 2025 |  | September 30, 2024
FV-NI: |  |  |  |  |  |  |
Realized gains | $ | 490 |  |  | $ | 38 |  |  | $ | 594 |  |  | $ | 163 |
Realized losses | 12 |  |  | 9 |  |  | 53 |  |  | 30 |
AFS: |  |  |  |  |  |  |
Realized gains | 17 |  |  | 6 |  |  | 32 |  |  | 11 |
Realized losses | 17 |  |  | 5 |  |  | 40 |  |  | 22 |
Progress Energy |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 88 |  |  | $ | — |  |  | $ | — |  |  | $ | 77 |
Equity securities | 2,455 |  |  | 6 |  |  | 3,579 |  |  | 2,367 |  |  | 28 |  |  | 3,482 |
Corporate debt securities | 10 |  |  | 3 |  |  | 384 |  |  | 4 |  |  | 6 |  |  | 272 |
Municipal bonds | 4 |  |  | 10 |  |  | 324 |  |  | 2 |  |  | 10 |  |  | 306 |
U.S. government bonds | 15 |  |  | 15 |  |  | 1,091 |  |  | 3 |  |  | 34 |  |  | 815 |
Other debt securities | — |  |  | — |  |  | 42 |  |  | — |  |  | — |  |  | 16 |
Total NDTF Investments | $ | 2,484 |  |  | $ | 34 |  |  | $ | 5,508 |  |  | $ | 2,376 |  |  | $ | 78 |  |  | $ | 4,968 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 14 |  |  | $ | — |  |  | $ | — |  |  | $ | 23 |
Municipal bonds | — |  |  | 1 |  |  | 24 |  |  | — |  |  | — |  |  | 24 |
Total Other Investments | $ | — |  |  | $ | 1 |  |  | $ | 38 |  |  | $ | — |  |  | $ | — |  |  | $ | 47 |
Total Investments | $ | 2,484 |  |  | $ | 35 |  |  | $ | 5,546 |  |  | $ | 2,376 |  |  | $ | 78 |  |  | $ | 5,015 |
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 88 |  |  | $ | — |  |  | $ | — |  |  | $ | 77 |
Equity securities | 2,455 |  |  | 6 |  |  | 3,579 |  |  | 2,367 |  |  | 28 |  |  | 3,482 |
Corporate debt securities | 10 |  |  | 3 |  |  | 384 |  |  | 4 |  |  | 6 |  |  | 272 |
Municipal bonds | 4 |  |  | 10 |  |  | 324 |  |  | 2 |  |  | 10 |  |  | 306 |
U.S. government bonds | 15 |  |  | 15 |  |  | 1,091 |  |  | 3 |  |  | 34 |  |  | 815 |
Other debt securities | — |  |  | — |  |  | 42 |  |  | — |  |  | — |  |  | 16 |
Total NDTF Investments | $ | 2,484 |  |  | $ | 34 |  |  | $ | 5,508 |  |  | $ | 2,376 |  |  | $ | 78 |  |  | $ | 4,968 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 14 |  |  | $ | — |  |  | $ | — |  |  | $ | 23 |
Municipal bonds | — |  |  | 1 |  |  | 24 |  |  | — |  |  | — |  |  | 24 |
Total Other Investments | $ | — |  |  | $ | 1 |  |  | $ | 38 |  |  | $ | — |  |  | $ | — |  |  | $ | 47 |
Total Investments | $ | 2,484 |  |  | $ | 35 |  |  | $ | 5,546 |  |  | $ | 2,376 |  |  | $ | 78 |  |  | $ | 5,015 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2025, and 2024, were as follows.
| Three Months Ended | Nine Months Ended
(in millions) | September 30, 2025 |  | September 30, 2024 |  | September 30, 2025 |  | September 30, 2024
FV-NI: |  |  |  |  |  |  |
Realized gains | $ | 358 |  |  | $ | 23 |  |  | $ | 421 |  |  | $ | 93 |
Realized losses | 9 |  |  | 10 |  |  | 49 |  |  | 34 |
AFS: |  |  |  |  |  |  |
Realized gains | 6 |  |  | 4 |  |  | 11 |  |  | 11 |
Realized losses | 3 |  |  | 3 |  |  | 17 |  |  | 22 |
Duke Energy Progress |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 72 |  |  | $ | — |  |  | $ | — |  |  | $ | 54 |
Equity securities | 2,330 |  |  | 6 |  |  | 3,445 |  |  | 2,256 |  |  | 28 |  |  | 3,362 |
Corporate debt securities | 10 |  |  | 3 |  |  | 367 |  |  | 4 |  |  | 6 |  |  | 256 |
Municipal bonds | 4 |  |  | 10 |  |  | 324 |  |  | 2 |  |  | 10 |  |  | 306 |
U.S. government bonds | 14 |  |  | 11 |  |  | 953 |  |  | 3 |  |  | 26 |  |  | 645 |
Other debt securities | — |  |  | — |  |  | 41 |  |  | — |  |  | — |  |  | 14 |
Total NDTF Investments | $ | 2,358 |  |  | $ | 30 |  |  | $ | 5,202 |  |  | $ | 2,265 |  |  | $ | 70 |  |  | $ | 4,637 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 9 |  |  | $ | — |  |  | $ | — |  |  | $ | 16 |
Total Other Investments | $ | — |  |  | $ | — |  |  | $ | 9 |  |  | $ | — |  |  | $ | — |  |  | $ | 16 |
Total Investments | $ | 2,358 |  |  | $ | 30 |  |  | $ | 5,211 |  |  | $ | 2,265 |  |  | $ | 70 |  |  | $ | 4,653 |
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 72 |  |  | $ | — |  |  | $ | — |  |  | $ | 54 |
Equity securities | 2,330 |  |  | 6 |  |  | 3,445 |  |  | 2,256 |  |  | 28 |  |  | 3,362 |
Corporate debt securities | 10 |  |  | 3 |  |  | 367 |  |  | 4 |  |  | 6 |  |  | 256 |
Municipal bonds | 4 |  |  | 10 |  |  | 324 |  |  | 2 |  |  | 10 |  |  | 306 |
U.S. government bonds | 14 |  |  | 11 |  |  | 953 |  |  | 3 |  |  | 26 |  |  | 645 |
Other debt securities | — |  |  | — |  |  | 41 |  |  | — |  |  | — |  |  | 14 |
Total NDTF Investments | $ | 2,358 |  |  | $ | 30 |  |  | $ | 5,202 |  |  | $ | 2,265 |  |  | $ | 70 |  |  | $ | 4,637 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 9 |  |  | $ | — |  |  | $ | — |  |  | $ | 16 |
Total Other Investments | $ | — |  |  | $ | — |  |  | $ | 9 |  |  | $ | — |  |  | $ | — |  |  | $ | 16 |
Total Investments | $ | 2,358 |  |  | $ | 30 |  |  | $ | 5,211 |  |  | $ | 2,265 |  |  | $ | 70 |  |  | $ | 4,653 |
Schedule of Realized Gain (Loss) | Realized gains and losses, which were determined on a specific identification basis, from sales of FV-NI and AFS securities for the three and nine months ended September 30, 2025, and 2024, were as follows.
| Three Months Ended | Nine Months Ended
(in millions) | September 30, 2025 |  | September 30, 2024 |  | September 30, 2025 |  | September 30, 2024
FV-NI: |  |  |  |  |  |  |
Realized gains | $ | 358 |  |  | $ | 23 |  |  | $ | 419 |  |  | $ | 93 |
Realized losses | 9 |  |  | 10 |  |  | 49 |  |  | 34 |
AFS: |  |  |  |  |  |  |
Realized gains | 5 |  |  | 4 |  |  | 10 |  |  | 11 |
Realized losses | 3 |  |  | 3 |  |  | 16 |  |  | 21 |
Duke Energy Florida |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 16 |  |  | $ | — |  |  | $ | — |  |  | $ | 23 |
Equity securities | 125 |  |  | — |  |  | 134 |  |  | 111 |  |  | — |  |  | 120 |
Corporate debt securities | — |  |  | — |  |  | 17 |  |  | — |  |  | — |  |  | 16 |
U.S. government bonds | 1 |  |  | 4 |  |  | 138 |  |  | — |  |  | 8 |  |  | 170 |
Other debt securities | — |  |  | — |  |  | 1 |  |  | — |  |  | — |  |  | 2 |
Total NDTF Investments(a) | $ | 126 |  |  | $ | 4 |  |  | $ | 306 |  |  | $ | 111 |  |  | $ | 8 |  |  | $ | 331 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 3 |
Municipal bonds | — |  |  | 1 |  |  | 24 |  |  | — |  |  | — |  |  | 24 |
Total Other Investments | $ | — |  |  | $ | 1 |  |  | $ | 25 |  |  | $ | — |  |  | $ | — |  |  | $ | 27 |
Total Investments | $ | 126 |  |  | $ | 5 |  |  | $ | 331 |  |  | $ | 111 |  |  | $ | 8 |  |  | $ | 358 |
(a)During the nine months ended September 30, 2025, and the year ended December 31, 2024, Duke Energy Florida received reimbursements from the NDTF for costs related to ongoing decommissioning activity of Crystal River Unit 3.
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are classified as FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  | December 31, 2024
| Gross |  | Gross |  |  |  | Gross |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  | Unrealized |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  | Holding |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  | Gains |  | Losses |  | Value
NDTF |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 16 |  |  | $ | — |  |  | $ | — |  |  | $ | 23 |
Equity securities | 125 |  |  | — |  |  | 134 |  |  | 111 |  |  | — |  |  | 120 |
Corporate debt securities | — |  |  | — |  |  | 17 |  |  | — |  |  | — |  |  | 16 |
U.S. government bonds | 1 |  |  | 4 |  |  | 138 |  |  | — |  |  | 8 |  |  | 170 |
Other debt securities | — |  |  | — |  |  | 1 |  |  | — |  |  | — |  |  | 2 |
Total NDTF Investments(a) | $ | 126 |  |  | $ | 4 |  |  | $ | 306 |  |  | $ | 111 |  |  | $ | 8 |  |  | $ | 331 |
Other Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 3 |
Municipal bonds | — |  |  | 1 |  |  | 24 |  |  | — |  |  | — |  |  | 24 |
Total Other Investments | $ | — |  |  | $ | 1 |  |  | $ | 25 |  |  | $ | — |  |  | $ | — |  |  | $ | 27 |
Total Investments | $ | 126 |  |  | $ | 5 |  |  | $ | 331 |  |  | $ | 111 |  |  | $ | 8 |  |  | $ | 358 |
(a)During the nine months ended September 30, 2025, and the year ended December 31, 2024, Duke Energy Florida received reimbursements from the NDTF for costs related to ongoing decommissioning activity of Crystal River Unit 3.
Duke Energy Indiana |
Debt Securities, Available-for-sale [Line Items] |
Debt Securities, Trading, and Equity Securities, FV-NI | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are measured at FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  |  |  | December 31, 2024
| Gross |  | Gross |  |  |  |  |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  |  |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  |  |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  |  |  | Losses |  | Value
Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  |  |  | $ | — |  |  | $ | 1 |
Equity securities | 5 |  |  | — |  |  | 51 |  |  |  |  | 4 |  |  | 89 |
Corporate debt securities | — |  |  | — |  |  | 1 |  |  |  |  | — |  |  | 6 |
Municipal bonds | — |  |  | 1 |  |  | 24 |  |  |  |  | 1 |  |  | 43 |
U.S. government bonds | — |  |  | — |  |  | 3 |  |  |  |  | — |  |  | 7 |
Total Investments | $ | 5 |  |  | $ | 1 |  |  | $ | 80 |  |  |  |  | $ | 5 |  |  | $ | 146 |
Debt Securities, Available-for-sale | The following table presents the estimated fair value of investments in debt and equity securities; equity investments are measured at FV-NI and debt investments are classified as AFS.
| September 30, 2025 |  |  |  | December 31, 2024
| Gross |  | Gross |  |  |  |  |  | Gross |  |
| Unrealized |  | Unrealized |  | Estimated |  |  |  | Unrealized |  | Estimated
| Holding |  | Holding |  | Fair |  |  |  | Holding |  | Fair
(in millions) | Gains |  | Losses |  | Value |  |  |  | Losses |  | Value
Investments |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents | $ | — |  |  | $ | — |  |  | $ | 1 |  |  |  |  | $ | — |  |  | $ | 1 |
Equity securities | 5 |  |  | — |  |  | 51 |  |  |  |  | 4 |  |  | 89 |
Corporate debt securities | — |  |  | — |  |  | 1 |  |  |  |  | — |  |  | 6 |
Municipal bonds | — |  |  | 1 |  |  | 24 |  |  |  |  | 1 |  |  | 43 |
U.S. government bonds | — |  |  | — |  |  | 3 |  |  |  |  | — |  |  | 7 |
Total Investments | $ | 5 |  |  | $ | 1 |  |  | $ | 80 |  |  |  |  | $ | 5 |  |  | $ | 146 |

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