ACEA S p A : Summary Data 1Q 2026 (summary data 1q2026)

‌ACEA GROUP 1Q 2026 RESULTS

KEY QUANTITATIVE DATA

1Q 2026 1Q 2025

1Q 2026 1Q 2025

1Q 2026 1Q 2025

1Q 2026 1Q 2025

1Q 2026 1Q 2025

* Of which photovoltaic: 40 GWh in 1Q 2026 and 40 GWh in 1Q 2025 1

‌ACEA GROUP 1Q 2026 RESULTS

STOCK MARKET

(euro)

ACEA 1Q 2065(€)

MARKET CAPITALIZATION

ACEA

+0.9%

FTSE MIB

-1.0%

MAX

(02/25/2026)

MIN

(03/20/2026)

(€MLN) (9/30/2025)

TSR 3/31/2025 ( VS 12/31/2025)

(Source Bloomberg, rebased to 100 as of 31 December 2025)

Changes in terms adjusted for the ex-dividend (Total Shareholder Return)

ACEA FTSE MIB

+0.9% -1.0%

2

vs 1Q 2025

Organic EBITDA pro-forma

Regulated2 EBITDA 95%

Organic Net Income

excl. public grants

pro forma4 3.31x

R E G U L A T E D E B I T D A A T 9 5 % O F T H E G R O U P ' S E B I T D A

N F P / E B I T D A R A T I O S T A B L E A T 3 . 3 x

Pro-forma revenues amounted to 0.7bn€ of which approximately 0.6bn€ related to regulated

businesses. Pro-forma revenues from regulated businesses aligned to the pro-forma 1Q 2025.

Pro-forma EBITDA at 342€m in line vs 1Q 2025 (+2€m, +1%) despite the perimeter change related to the 2025 asset rotation (divestment of the High Voltage business and photovoltaic assets).

Organic pro-forma EBITDA3 at 344€m, +14€m (+4%) vs 1Q 2025 mainly driven by the growth in Regulated Activities.

Net income at 111€m, +13€m (+13%) vs 1Q 2025.

Organic Net income3 at 82€m, +10€m (+14%) vs 1Q 2025 also, thanks to the growth in

operating results of the regulated businesses.

Capex net of public contributions to 286€m (+18%) vs 1Q 2025.

Including investments made with the support of public grants, total capex reached 302€m (+15%) vs 1Q 2025.

Operating free cashflow at -91€m. The achieved results confirm a solid financial structure with

pro-forma Net Debt/EBITDA LTM to 3.31x.

1. In accordance with IFRS 5, Acea Energia is classified as a "discontinued operation" in 1Q26 results as the divestment was completed on April 10, 2026. This classification entails, among the others, the synthetic consolidation of Acea Energia's income statement represented in a single separate item in Acea's consolidated income statement, "Profit/(loss) from discontinued operating activities". To provide a more meaningful analysis of the Acea Group's financial performance, Acea's pro forma consolidated income statements for the periods ended March 31 and 2025 (the "Pro Forma Consolidated Statements") have been prepared. These statements simulate, using valuation criteria consistent with those adopted by the Company, the main economic effects of the Sale, restoring intercompany transactions with discontinued operations in order to obtain a representation of the results of continuing operations as if the discontinued operations had been deconsolidated. In particular, regarding the elimination of intercompany balances between continuing operations and discontinued operations, the following pro forma adjustments have been made: i) the income statement balances for the periods in question relating to transactions between Acea group companies and Acea Energia have been reinstated, as it is believed that these operations will continue even after the disposal (such balances, where applicable, have in fact been eliminated in the consolidation process). For 1Q26, reported revenues and EBITDA reached 717.7 €m and 329.4 €m, respectively. | 2. Regulated businesses include, in addition to the regulated Water Italy and Networks businesses, Public Lighting and Environment. | 3. Excluding one-off items and perimeter changes. |

4. The pro-forma Net Debt/EBITDA ratio considers the proceeds from the disposal of ACEA Energia while it does not include the EBITDA of the divested activities.

3

‌ACEA GROUP 1Q 2026 RESULTS

K E Y F I N A N C I A L S T R U C T U R E A N D R A T I N G S

NET DEBT DIC 2025-1Q 2026 €m

Rating

vs DIC 25

DIC 25 1Q 26 ∆ 1Q 26

NET DEBT pro-forma1 4,567 4,646 79

Long-term debt 4,926 4,926

Short-term debt 667 618

« B B B + »

O u t l o o k S t a b l e

«B a a 1 » O u t l o o k S t a b l e

Pro-forma Cash and cash equivalents1

(1,026) (898)

Sustainability Rating (updated May 2026)

4

1. Pro-forma Net Debt considers the effect of the collection of the proceeds for the disposal of ACEA Energia (impact amounting to €430m in 1Q2026 compared to €396m in FY2025, difference mainly

attributable to the change of the Net Financial Position of the disposed perimeter).

2