ISRE 2410: Review of Interim Financial Information

ISRE 2410 is the international standard that governs how a company’s own independent annual auditor reviews its interim financial statements — the quarterly or half-year figures published between full-year audits.¹ Issued by the International Auditing and Assurance Standards Board, its full title is “Review of Interim Financial Information Performed by the Independent Auditor of the Entity.” The review gives investors a form of independent assurance on interim numbers, but a lighter and cheaper form than a full audit: the auditor relies mainly on inquiry and analytical procedures and expresses a negatively worded conclusion rather than an audit opinion.

What Counts as Interim Financial Information

Interim financial information is any complete or condensed set of financial statements covering a period shorter than the entity’s full financial year.² In practice that usually means quarterly or half-year reports issued by listed companies to meet regulatory or market obligations.

These statements must follow the same accounting policies as the entity’s most recent annual financial statements unless a policy change is specifically justified and disclosed. Producing a fresh full audit every three months would be neither timely nor affordable, and that gap is exactly what the review engagement is built to fill.

Who Can Perform an ISRE 2410 Review

This is the detail people most often miss. ISRE 2410 applies only when the reviewer is also the entity’s annual auditor. Throughout the standard, “the auditor” means the firm that audits the year-end accounts.²

The reason is practical. An auditor who already knows the entity’s books, systems, and risks knows what “normal” looks like, and that baseline is what makes analytical procedures effective within a short review timeframe. If a practitioner who is not the annual auditor is engaged to review financial statements, a different standard applies — ISRE 2400 — with its own procedures for building that understanding from scratch.²

Ethical requirements are identical to those on the annual audit: independence, integrity, objectivity, professional competence, confidentiality, and professional behavior.² The lower level of assurance does not come with a lower independence bar.

Limited Assurance, Not an Audit Opinion

The difference between a review and an audit is the level of assurance. An audit provides reasonable assurance and is expressed positively: the statements are “presented fairly, in all material respects.” A review provides limited assurance and is expressed negatively: “nothing has come to our attention that causes us to believe” the interim financial information is materially misstated.²

That wording is not a formality. It reflects the work behind it. An audit actively searches for material misstatement through evidence-gathering, transaction testing, and evaluation of controls. A review checks whether anything surfaces during a structured but far lighter examination. It is designed to catch obvious inconsistencies and significant red flags, not misstatements that would only emerge from detailed substantive testing.

What the Auditor Actually Does

The engagement rests on two procedural pillars: inquiry and analytical procedures.²

Inquiry

The auditor talks primarily with people responsible for financial and accounting matters. The conversations cover the accounting policies applied to the interim figures, any significant or unusual transactions in the period, changes in internal controls, and how management put the interim numbers together. The auditor also reads the minutes of shareholder, board, and relevant committee meetings to pick up anything that could affect the interim information.² Where minutes are not available, the auditor asks about what was discussed.

Analytical Procedures

The auditor compares the interim figures against prior comparable periods, budgets and forecasts, and industry trends. The point is to identify relationships or amounts that behave differently from what would be expected. When something looks off, that triggers further inquiry to work out whether the deviation reflects a real event, a policy change, or a possible error.

What the Review Does Not Include

A review deliberately excludes detailed testing of internal controls, physical inspection of assets, third-party confirmations of balances, and substantive testing of individual transactions. Those procedures belong to the annual audit.³ If inquiry and analytical work produce reason to believe the information may be materially misstated, however, the auditor is required to extend procedures until the concern is either resolved or reflected in the report.

Subsequent Events and Written Representations

The auditor asks management whether it has identified events between the interim balance sheet date and the date of the review report that may need adjustment or disclosure. Separate procedures to hunt for events after the report date are not required, but transactions clustered at the boundary of the interim period warrant specific attention.²

Management must also give the auditor written representations confirming its responsibility for the interim financial information, the completeness of information provided, and disclosure of significant subsequent events.² These are not optional. Without them, the engagement cannot be completed.

How Materiality Is Set for the Interim Period

Materiality in a review is not the same as in a year-end audit. Because the interim period is shorter and the totals smaller, thresholds are typically lower than for the full-year statements. An item that would be immaterial against twelve months of revenue can be significant against a single quarter.

The auditor exercises professional judgment on both quantitative and qualitative factors when setting the materiality level. Where the applicable financial reporting framework defines materiality, that definition anchors the assessment. Either way, materiality is measured against the interim data, not against annualized figures.

The Review Report and Its Possible Conclusions

The report identifies the interim financial information reviewed, states that management is responsible for preparing it, describes the scope of the review, and makes explicit that the engagement is substantially less in scope than an audit and that no audit opinion is expressed.

Unmodified Conclusion

When the auditor finds no material issues, the report contains an unmodified conclusion using negative assurance language: “Based on our review, nothing has come to our attention that causes us to believe that the accompanying interim financial information is not prepared, in all material respects, in accordance with [the applicable financial reporting framework].”²

Modified Conclusions

Where problems surface, three forms of modification are available:

A qualified conclusion, used when the auditor identifies a material departure from the applicable financial reporting framework whose effect is not so widespread that it undermines the interim information as a whole. It is also used in rare cases where a scope limitation not imposed by management is confined to specific matters that are material but not pervasive.
An adverse conclusion, used when the departure from the framework is both material and pervasive, so that a qualified conclusion would understate the problem.
A disclaimer of conclusion, used when management imposes a scope limitation that prevents the review from being completed. If a legal or regulatory requirement forces the auditor to issue a report anyway, the auditor disclaims a conclusion rather than provide assurance on incomplete work.

Modified conclusions are uncommon in practice, because management usually corrects identified issues before the report is finalized. When they do appear, they signal serious concerns.²

Where ISRE 2410 Does Not Apply: U.S. SEC Filers

For companies filing with the U.S. Securities and Exchange Commission, interim financial statements included in quarterly Form 10-Q filings must be reviewed by an independent public accountant before filing, but the review is governed by PCAOB Auditing Standard AS 4105, not ISRE 2410.⁴

The two standards take the same fundamental approach. AS 4105 also relies on analytical procedures and inquiries rather than substantive testing, and the accountant’s objective under it is to determine “whether he or she is aware of any material modifications that should be made to the interim financial information for it to conform with generally accepted accounting principles.”³ Where a company states in its filing that its interim statements have been reviewed, the accountant’s review report must be filed alongside them.⁴

For companies reporting under IFRS outside the United States, ISRE 2410 is the directly applicable standard, and many jurisdictions have adopted it with minor local modifications. The practical differences between the two regimes are small enough that a reader comparing review reports across jurisdictions can expect broadly comparable levels of assurance.