Pampa Energy Inc.

Comparative information

The information as of December 31, 2025 and for the nine and three-month periods ended September 30, 2025, disclosed for comparative purposes, arises from the Consolidated Financial Statements as of those dates.

Additionally, certain non-significant reclassifications have been made to the Consolidated Financial Statements´ figures disclosed for comparative purposes to keep the consistency in the presentation with the current period figures.

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

NOTE 4: ACCOUNTING POLICIES

The accounting policies applied in these Consolidated Condensed Interim Financial Statements are consistent with those used in the Consolidated Financial Statements for the last fiscal year, which ended on December 31, 2025.

4.1 New accounting standards, amendments and interpretations issued by the IASB effective as of December 31, 2026 and adopted by the Company

The Company has applied the following standards and / or amendments for the first time as of January 1, 2026:

The application of the detailed standards and amendments did not have any impact on the results of the operations or the financial position of the Company.

4.2 New accounting standards, amendments and interpretations issued by the IASB not yet effective and not early adopted by the Company

Pursuant to CNV General Resolution No. 972/23, early application of IFRS accounting standards and/or amendments thereto is not permitted unless specifically permitted at the time of adoption.

As of September 30, 2026, the Company has not early applied the following standards and/or amendments:

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

NOTE 4:(Continuation)

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

NOTE 5: GROUP STRUCTURE

Unless otherwise indicated, the country is also the principal place where the subsidiary carries out its activities.

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

The following table presents the main activity and the financial information used for valuation and percentages of participation in associates and joint ventures:

(1)The Company holds a 50% interest in CIESA, a company that holds a 53.83% interest in TGS’s capital stock; therefore, the Company has a 26.91% interest in TGS.

As of September 30, 2026, TGS’s common shares and ADR traded on the BCBA and NYSE were listed at $ 8,375.00 and US$ 25.95, respectively, conferring Pampa’s holding an approximate market value of US$ 1,051 million ($ 1,696,744 million).

(2)The Company has a 50% interest in Citelec, a company that holds a 52.65% interest in Transener’s capital stock; therefore, the Company has a 26.33% indirect interest in Transener. As of September 30, 2026, Transener’s common share price listed at the BCBA was $ 3,100, conferring Pampa’s indirect holding an approximate market value of US$ 239 million ($ 362,887 million).

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

The detail of the balances of investments in associates and joint ventures is as follows:

The following table shows the breakdown of the result from investments in associates and joint ventures:

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

The evolution of investments in associates and joint ventures is as follows:

Reversal of impairment losses on non-financial assets

During the quarter ended June 30, 2026, CTB identified significant changes in the environment where it operates and, consequently, determined CTEB’s recoverable amount as of June 30, 2026.

The recoverability assessment resulted in the reversal of impairment losses recognized in previous fiscal years, with a US$ 31 million impact on the Company’s share of profit from associates and joint ventures for the period.

Perito Moreno Gas Pipeline (GPM) Expansion

MECON Resolution No. 676/26 approved the application to opt into the RIGI for the GPM expansion project, effective as of April 30, 2026.

TGS conducted a public call for tenders to award a portion of the incremental transportation capacity associated with the expansion of the GPM and on April 15, 2026, 5.4 million m³/day were awarded. The remaining capacity was awarded on August 26, 2026.

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

Integral NGL Project

On June 10, 2026, TGS’s Board of Directors approved the development of the Integral NGL Project, which is structured into two independent, but operationally linked, single projects representing successive stages of the processing, fractionating, obtaining and storing of natural gas liquids, and the subsequent product dispatch and export.

The Integral NGL Project will be executed through the following companies controlled by TGS and established as SPV within RIGI’s framework:

(i) Procesadora de Gas del Sur S.A. (“PGS”): in charge of the so-called separation project, consisting of the construction, operation and maintenance of a natural gas processing plant located in Tratayén, Province of Neuquén, and a natural gas stream segregation pipeline, which will enable the provision of natural gas gathering and processing services to gas producers; and

(ii) Midstream de Gas del Sur S.A. (“MGS”): in charge of the transportation, fractionation, storage and commercialization project, comprising the construction, operation and maintenance of a multiproduct pipeline connecting the Tratayén Plant with a fractionation plant in the Bahía Blanca area, Province of Buenos Aires, together with storage and dispatch facilities. Under the project, MGS will acquire the natural gas liquids mix resulting from PGS’s processing for its transportation, fractionation into commercial products (such as propane, butane and natural gasoline), storage and subsequent sale to export customers.

The project is structured through long-term agreements, including execution, transportation and processing, liquid hydrocarbon purchase and sale, and commercial cooperation agreements.

TGS has granted corporate guarantees and surety bonds to secure certain obligations arising from the agreements entered into with the producers participating in the project and from the financing agreements obtained by MGS and PGS for the project’s development.

Weather event

During the period ended September 30, 2026, TGS recorded $ 9,586 million losses arising from expenses related to the weather event of March 7, 2025, which resulted in the flooding of the Cerri Complex, and received $ 13,716 million from insurance companies as an advance payment on account of the final settlement of the claim.

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

San Matías Pipeline Project

In addition to the gas liquefaction project to be developed by SESA, which includes the installation of two liquefaction vessels in the Gulf of San Matías, SMP will be responsible for the construction and operation of a dedicated pipeline connecting gas production from Vaca Muerta, in Neuquén, to the Gulf of San Matías, in Río Negro, to supply the liquefaction vessels intended for LNG exports. The project involves the construction of an approximately 470-km-long, 36-inch-diameter pipeline with a transportation capacity of up to 28 million m³/day. The estimated investment amounts to US$ 1.3 billion, and the pipeline is expected to be commissioned in the second quarter of 2028.

MECON Resolution No. 873/26 approved the application to opt into the RIGI for the project undertaken by SMP, effective as from June 1, 2026.

Syndicated international loan

In August 2026, SMP entered into a syndicated international loan with a consortium of financial institutions for a total amount of up to US$ 900 million to finance the construction and development of the project. The financing has a 7-year term and accrues interest at a rate of Term SOFR plus a 4.25% annual margin.

SMP may request disbursements on a monthly basis until completion of the project or the first amortization date, scheduled for December 31, 2029, whichever occurs first. As of September 30, 2026, the banks have made disbursements totaling US$ 118 million.

To secure its obligations, SMP granted certain collateral under the financing, including the following: (i) it assigned its collection rights under the transportation agreement entered into with SESA, and (ii) SMP’s shareholders (including the Company) have executed a fiduciary assignment of their shares as collateral for the financing, which will remain in effect until the loan is repaid.

As of September 30, 2026, SMP has complied with all covenants undertaken under the syndicated loan agreement.

Issuance of Class 1 CB

On September 22, 2026, VMOS issued limited-recourse Class 1 CB with a face value of US$ 233.7 million, at a 6.25% fixed annual interest rate and maturing on September 22, 2030.

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

Net proceeds will be used to finance the development, construction and operation of the VMOS Project, including working capital and investments related to the construction work.

VMOS has undertaken certain commitments regarding the creation of collateral and/or restrictions on certain rights. In particular, it has committed to perfecting an assignment as collateral of all present and future collection rights corresponding to the dollar-linked tariff under the initial transportation agreements and the designated transportation agreement, to secure the payment of principal and interest on the Class 1 CB. As of the date of issuance of these Consolidated Condensed Interim Financial Statements, VMOS has not yet perfected such assignment as collateral.

Assets and liabilities as of September 30, 2026 and December 31, 2025 and the production cost of the Joint Operations and Consortiums in which the Company participates corresponding to the nine-month periods ended September 30, 2026 and 2025 are detailed below:

It is worth highlighting that the information presented does not include charges recorded by the Company as a member of the Joint Operations and Consortiums.

Relinquishment process for the Veta Escondida block

Provincial Executive Order No. 605/26 approved the Settlement Agreement entered into between the Province of Neuquén and Pampa on March 4, 2026, which set aside the executive order declaring the termination of the Veta Escondida block´s concession. In addition, the parties agreed to conclude the process for relinquishing the block to the Province. Within this framework, the Company and Total Austral (co-concessionaire) are jointly carrying out such process in an orderly manner, with the Company being responsible for the abandonment of wells and facilities and the required environmental remediation works.

NOTES TO THE UNAUDITED CONSOLIDATED CONDENSED INTERIM FINANCIAL STATEMENTS (Continuation)For the nine-month period ended September 30, 2026, presented on comparative basis. (In millions of US$ – unless otherwise stated)

NOTE 6: RISKS