Vista Energy B de C : 2023 Audited Consolidated Financial Statements

VISTA ENERGY, S.A.B. DE C.V.

Consolidated financial statements as of December 31, 2023 and 2022,

and for the years ended December 31, 2023 and 2022

Av. Ejército Nacional 843-B	Tel: [phone]
Antara Polanco	Fax: [phone]
11520 Mexico, D.F.	ey.com/mx

INDEPENDENT AUDITOR'S REPORT

The Board of Directors and Shareholders of Vista Energy, S.A.B. de C.V. Report on the audit of the financial statements

Opinion

We have audited the accompanying consolidated financial statements of Vista Energy, S.A.B. de C.V. and its subsidiaries (collectively the "Company"), which comprise the consolidated statement of financial position as of December 31, 2023; and the consolidated of profit or loss and other comprehensive income; consolidated statement of changes in equity; and consolidated statement of cash flows for the year ended at that date, and notes to the consolidated financial statements, including a summary of material accounting policies.

In our opinion, the accompanying consolidated financial statements present fairly, in all material respects, the consolidated financial position of Vista Energy, S.A.B. de C.V. as of December 31, 2023, its consolidated financial performance and its consolidated cash flows for the period ended at that date, in accordance with International Financial Reporting Standards ("IFRS"), as issued by the International Accounting Standards Board.

Basis for opinion

We conducted our audit in accordance with International Standards on Auditing ("ISAs"). Our responsibilities under those standards are described in the "Auditor's Responsibilities for the Audit of the Consolidated Financial Statements" section of our report. We are independent of the Company in accordance with the International Code of Ethics for Professional Accountants (including International Independence Standards) ("IESBA Code") together with the ethical requirements that are relevant to our audit of the consolidated financial statements in Mexico according to the "Codigo de Etica Profesional del Instituto Mexicano de Contadores Publicos" ("IMCP Code"), and we have fulfilled our other ethical responsibilities in accordance with these requirements and the IESBA Code.

We believe that the audit evidence we have obtained is sufficient and appropriate to provide a basis for our opinion.

Key audit matters

Key audit matters are those matters that, in our professional judgment, were of most significance in the audit of the consolidated financial statements of the current period. These matters were addressed in the context of the audit of the consolidated financial statements as a whole and in forming the auditor's opinion thereon, and we do not provide a separate opinion on these matters. For each matter below, our description of how our audit addressed the matter is provided in that context.

We have fulfilled the responsibilities described in the "Auditor's Responsibilities for the Audit of the Consolidated Financial Statements" section of our report, including in relation to these matters. Accordingly, our audit included the performance of procedures designed to respond to our assessment of the risks of material misstatement of the consolidated financial statements. The results of our audit procedures, including the procedures performed to address the matters below, provide the basis for our audit opinion on the accompanying consolidated financial statements.

Depreciation, depletion, and amortization of property, plant, and equipment

Description of the key audit matter

As described in Note 13 to the financial statements, as of December 31, 2023, property, plant and equipment amounted to thousands of US$ 1,927,759 and have an associated depreciation, depletion and amortization charge of thousands of US$ 831,660. As described in Note 2.4.2.2, the Company uses the successful effort method to account for its assets for oil and gas development and exploitation. Depreciation of oil and gas assets is calculated using the production unit method based on proven oil and gas reserves, as estimated by the Company's reserve engineers.

Oil and gas reserves are those volumes of natural gas, crude oil, and liquefied natural gas that, through analysis of geology and engineering data, can be estimated with reasonable certainty to be economically exploitable at a given date, in known reservoirs, and under current economic conditions, operating methods, and government regulations. The Company's reserve engineers evaluate geological and engineering data when estimating oil and gas reserves. Estimating reserves also requires the selection of assumptions, including assumptions about oil and gas prices, operating costs, and future capital outlays, among others. Due to the complexity involved in estimating oil and gas reserves, Management engaged independent reserve engineers to certify the proven oil and gas reserve estimates prepared by the Company's in-house reserve engineers as of December 31, 2023.

Auditing the calculation of the Company's depreciation, depletion and amortization is complex due to the use of the work of the internal reserve engineers and the independent engineers and the evaluation by the Management of the premises used mentioned above.

How our audit addressed the key audit matter

Our audit procedures included, but were not limited to, (i) understanding the process of calculating depreciation, use, and amortization of property, plant, and equipment, including management's process on the completeness and accuracy of financial data provided to engineers in estimating proven oil and gas reserves; (ii) the evaluation of the professional qualifications and objectivity of the Company's in-house reserve engineers, who are responsible for the preparation of reserve estimates, and of the independent reserve engineers who certified such estimates, (iii) the evaluation of the completeness and review of the financial data used by the engineers for the estimation of proven oil and gas reserves, and

1. the analysis of its consistency with supporting documentation, and the identification and analysis of other corroborative or contradictory evidence. In addition, we tested the arithmetic calculation of depreciation, use and amortization, and compared the amounts of oil and gas reserves used in such calculation with the Company's proven reserves reports.

Finally, we evaluated the reasonableness of the disclosures included in the Company's accompanying consolidated financial statements as of December 31, 2023.

Recognition of gain on the transfer of conventional assets

Description of the key audit matter

As of December 31, 2023, the Company recognized a gain of thousands of US$ 89,659 as a result of the transfer of the operation of certain producing concessions in the Argentine Neuquén basin ("Conventional Assets") which arises from the difference between the value of the agreed consideration and the derecognition of the residual value of the net Conventional Assets transferred. As described in Note 1.2.1 to the financial statements, the Company recognized an account receivable for the aforementioned agreed consideration that is equivalent to the discounted value of the funds receivable and the volumes of crude oil, natural gas and liquefied natural gas to be made available within a specified period of time.

The determination of the profit and the initial valuation of the related receivable, involved significant judgments and estimates by management, given the degree of uncertainty associated primarily with the expected timing of production availability. In particular, the estimate of the account receivable has been sensitive to operating costs, future production of Conventional Assets and the applicable discount rate, which are subjective assumptions affected by Management's expectations about the future performance of such assets and industry conditions.

How our audit addressed the key audit matter

Our audit procedures included, but were not limited to, (i) understanding the process followed by management for the determination of the receivable and the recognition of the gain derived from this transaction, (ii) the analysis of the key considerations used by management for the determination of the discounted value of funds, and (iii) the timing of the availability of crude oil volumes, natural gas and liquefied natural gas. For example, we evaluate the operating cost estimate against actual costs and compare assumptions about the timing of production availability with the oil and gas reserve estimate certified by independent reserve engineers. In addition, we involve our specialists in reviewing the discount rate used.

Finally, we evaluated the reasonableness of the disclosures included in the Company's accompanying consolidated financial statements as of December 31, 2023.

Other information included in the Compnay's 2023 Annual Report

Other information consists of the information included in the Company's 2023 Annual Report to be presented to the stockholders and the Annual Report to be presented to the Comision Nacional Bancaria y de Valores ("CNBV"), other than the financial statements and our auditor's report thereon. Management is responsible for the other information. The other information is expected to be made available to us after the date of this auditor's report.

Our opinion on the consolidated financial statements does not cover the other information and we do not express any form of assurance conclusion thereon.

In connection with our audit of the consolidated financial statements, our responsibility is to read the other information identified above when it becomes available and, in doing so, consider whether the other information is materially inconsistent with the consolidated financial statements or our knowledge obtained in the audit or otherwise appears to be materially misstated.

When we read and consider the Annual Report submitted to the CNBV and the annual report submitted to shareholders, we conclude that it contains a material deviation, we are obliged to communicate the matter to those responsible for the governance of the Company and issue the statement on the Annual Report required by the CNBV, in which the matter will be described.

Responsibilities of Management and the Audit Committee for the Consolidated Financial Statements

Management is responsible for the preparation and fair presentation of the accompanying consolidated financial statements in accordance with IFRS, and for such internal control as management determines is necessary to enable the preparation of the consolidated financial statements that are free from material misstatement, whether due to fraud or error.

In preparing the consolidated financial statements, management is responsible for assessing the Company's ability to continue as a going concern, disclosing, as applicable, matters related to going concern and using the going concern basis of accounting unless management either intends to liquidate the Company or to cease operations, or has no realistic alternative but to do so.

The Audit Committee is responsible for overseeing the Company's financial reporting process.

Auditor's Responsibilities for the Audit of the Consolidated Financial Statements

Our objectives are to obtain reasonable assurance about whether the consolidated financial statements as a whole are free from material misstatement, whether due to fraud or error, and to issue an auditor's report that includes our opinion. Reasonable assurance is a high level of assurance but is not a guarantee that an audit conducted in accordance with ISAs will always detect a material misstatement when it exists. Misstatements can arise from fraud or error and are considered material if, individually or in the aggregate, they could reasonably be expected to influence the economic decisions of users taken based on these consolidated financial statements.

As part of an audit in accordance with ISAs, we exercise professional judgment and maintain professional skepticism throughout the audit. We also:

• Identify and assess the risks of material misstatement of the consolidated financial statements whether due to fraud or error, design and perform audit procedures responsive to those risks and obtain audit evidence that is sufficient and appropriate to provide a basis for our opinion. The risk of not detecting a material misstatement resulting from fraud is higher than for one resulting from error, as fraud may involve collusion, forgery, intentional omissions, misrepresentations, or the override of internal control.
• Obtain an understanding of internal control relevant to the audit in order to design audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control.

• Evaluate the appropriateness of accounting policies used and the reasonableness of accounting estimates and related disclosures made by management.
• Conclude on the appropriateness of management's use of the going concern basis of accounting and, based on the audit evidence obtained, whether a material uncertainty exists related to events or conditions that may cast significant doubt on the Company's ability to continue as a going concern. If we conclude that a material uncertainty exists, we are required to draw attention in our auditor's report to the related disclosures in the consolidated financial statements or, if such disclosures are inadequate, to modify our opinion. Our conclusions are based on the audit evidence obtained up to the date of our auditor's report. However, future events or conditions may cause the Company to cease to continue as a going concern.
• Evaluate the overall presentation, structure and content of the consolidated financial statements, including the disclosures, and whether the consolidated financial statements represent the underlying transactions and events in a manner that achieves fair presentation.
• Obtain sufficient appropriate audit evidence regarding the financial information of the entities or business activities within the Company to express an opinion on the consolidated financial statements. We are responsible for the direction, supervision and performance of the Company audit. We remain solely responsible for our audit opinion.

We communicate with the Audit Committee regarding, among other matters, the planned scope and timing of the audit and significant audit findings, including any significant deficiencies in internal control that we identify during our audit.

We also provide the Audit Committee with a statement that we have complied with relevant ethical requirements regarding independence and to communicate with them all relationships and other matters that may reasonably be thought to bear on our independence, and where applicable, actions taken to eliminate threats or safeguards applied.

From the matters communicated with the Audit Committee, we determine those matters that were of most significance in the audit of the consolidated financial statements of the current period and are therefore the key audit matters. We describe these matters in our auditor's report unless law or regulation precludes public disclosure about the matter or when, in extremely rare circumstances, we determine that a matter should not be communicated in our report because the adverse consequences of doing so would reasonably be expected to outweigh the public interest benefits of such communication.

The partner in charge of the audit resulting in this independent auditor's report, is who signs it.

Mancera, S.C.

A member practice of

Ernst & Young Global Limited

Arturo Figueroa Carmona

Mexico City, Mexico

March 11, 2024

VISTA ENERGY, S.A.B. DE C.V.

Consolidated financial statements as of December 31, 2023 and 2022, and for the years ended December 31, 2023 and 2022

TABLE OF CONTENTS

• Consolidated statements of profit or loss and other comprehensive income for the years ended December 31, 2023 and 2022
• Consolidated statements of financial position as of December 31, 2023 and 2022
• Consolidated statements of changes in equity for the years ended December 31, 2023 and 2022
• Consolidated statements of cash flows for the years ended December 31, 2023 and 2022
• Notes to the consolidated financial statements as of December 31, 2023 and 2022, and for the years ended December 31, 2023 and 2022

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VISTA ENERGY, S.A.B. DE C.V.

Consolidated statements of profit or loss and other comprehensive income for the years ended December 31, 2023 and 2022

(Amounts expressed in thousands of US Dollars)

	Notes	Year ended		Year ended
	December 31, 2023		December 31, 2022
Revenue from contracts with customers	5	1,168,774	1,187,660
Cost of sales:
Operating costs	6.1	(94,685)	(133,385)
Crude oil stock fluctuation	6.2	(2,058)	(500)
Depreciation, depletion and amortization	13/14/15	(276,430)	(234,862)
Royalties and others	6.3	(176,813)	(188,677)
Other non-cash costs related to the transfer of conventional assets	1.2.1	(27,539)		-
Gross profit		591,249		630,236
Selling expenses	7	(68,792)	(59,904)
General and administrative expenses	8	(70,483)	(63,826)
Exploration expenses	9	(16)	(736)
Other operating income	10.1	203,812	26,698
Other operating expenses	10.2	302	(3,321)
Impairment of long -lived assets	3.2.2	(24,585)		-
Operating profit		631,487		529,147
Interest income	11.1	1,235	809
Interest expense	11.2	(21,879)	(28,886)
Other financial income (expense)	11.3	(65,484)		(67,556)
Financial income (expense), net		(86,128)		(95,633)
Profit before income tax		545,359		433,514
Current income tax (expense)	16	(16,393)	(92,089)
Deferred income tax (expense)	16	(132,011)		(71,890)
Income tax (expense)		(148,404)		(163,979)
Profit for the year, net		396,955	269,535
Other comprehensive income
Other comprehensive income that shall not be reclassified to profit
(loss) in subsequent periods
- Profit (loss) from actuarial remeasurement related to employee	23	6,565	(4,181)
benefits
- Deferred income tax (expense) benefit	16	(2,298)	1,463
Other comprehensive income that shall not be reclassified to
profit (loss) in subsequent years, net of taxes		4,267		(2,718)
Total comprehensive profit for the year		401,222	266,817
Earnings per share
Basic (in US Dollars per share)	12	4.237	3.068
Diluted (in US Dollars per share)	12	4.000	2.755

Notes 1 through 34 are an integral part of these consolidated financial statements

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