How to Find and Verify a PCAOB-Registered Auditor

Why PCAOB registration is the first filter

Under the Sarbanes-Oxley Act, a public accounting firm that prepares or issues audit reports for issuers must be registered with the PCAOB. For an SEC reporting company, an audit report from an unregistered firm is not a usable audit report. The same logic now extends into the over-the-counter market: the current OTCQB Rules and OTCQX Rules for U.S. Companies both require annual audits to be performed by a PCAOB-registered auditor, subject to narrow exceptions (see our OTCQB vs. OTCQX comparison).

Registration is necessary, but it is only a license to practice before the PCAOB. It says nothing about capacity, industry knowledge or inspection results. That is why the rest of this guide matters.

Step 1: Confirm registration status and the Firm ID

Start on the PCAOB's Registered Firms page, which lets you find currently registered firms by name, location or audit report activity. Each firm has a Firm Summary page that brings together its registration details, annual and special report filings, inspection reports and disciplinary information. The underlying filings sit in the PCAOB's Registration, Annual and Special Reporting (RASR) system.

What to confirm:

• The exact legal name matches the name on the proposal and engagement letter.
• The PCAOB Firm ID matches the one the firm gives you. Annual reports on EDGAR also tag the auditor's name, location and PCAOB ID in their audit information data, so you can cross-check it against the firm's existing clients.
• The firm is listed as currently registered, not pending withdrawal. The PCAOB separately publishes firms that have requested withdrawal (Form 1-WD) and notices of disapproved applications.
• The office location that will perform the work, especially if the firm has several offices or affiliates.

We apply the same standard to ourselves. SESGLO is the PCAOB audit practice of Asesoria Global, Sociedad Anónima, and we invite every prospective client to look up our registration using PCAOB Firm ID 7184 before our first call. Our quality control page explains how our system of quality control is organized.

Step 2: Use AuditorSearch and Form AP data

AuditorSearch is the PCAOB's public database of issuer audit engagements. It is built from Form AP, which a registered firm must file for each audit report it issues for an issuer under PCAOB Rule 3211. The PCAOB says the dataset is updated daily and can be downloaded in full.

Form AP discloses:

• The engagement partner who led the audit, by name and partner ID.
• Other accounting firms that took part in the audit. The name, location and extent of participation must be disclosed individually for each firm whose work was 5% or more of total audit hours; firms below 5% are reported in aggregate.
• The issuer and the audit report the form relates to.

A Form AP is generally due 35 days after the audit report is first included in a document filed with the SEC, or 10 days after if the report is first included in a registration statement for an initial public offering.

How to use it in auditor selection:

• Search by firm to see which issuers it audits today and how that list has changed over time.
• Search by the partner the firm proposes, to see how many issuer audits that person signs.
• Look at the "other accounting firms" data. Heavy reliance on other firms is not wrong in itself, but you should know who will do the work and where.

Step 3: Understand registration versus inspection

Registration and inspection are different things. According to the PCAOB's inspection procedures, the Board inspects annually firms that regularly provide audit reports for more than 100 issuers, and inspects firms that provide audit reports for 100 or fewer issuers at least once every three calendar years, with limited exceptions under PCAOB Rule 4003. Most firms that serve small-cap and OTC companies are on the triennial cycle.

Two practical consequences:

• A firm that registered recently, or only recently began issuing issuer audit reports, may not yet have a public inspection report. That is not a red flag in itself, but ask the firm about it directly.
• A report can be two or three years old. Check its date and ask what has changed since.

How to read an inspection report

Public inspection reports are on the PCAOB's Firm Inspection Reports page, which you can search and filter. The PCAOB says plainly that an inspection report is not intended as a balanced report card or overall rating. Read it with that in mind:

• Part I.A describes audits with deficiencies the inspection staff considered significant enough that the firm, in their view, had not obtained sufficient appropriate audit evidence to support its opinion.
• Part I.B covers deficiencies that do not relate directly to the sufficiency or appropriateness of the evidence, for example certain required communications or documentation matters.
• Part I.C covers instances of potential non-compliance with SEC independence rules or non-compliance with PCAOB independence rules.
• Part II covers criticisms of, or potential defects in, the firm's quality control system. Under the Sarbanes-Oxley Act, these portions are not made public if the firm addresses them to the Board's satisfaction within 12 months after the report is issued. If Part II is public, the firm did not satisfy the Board on that point within the period.

Look for patterns rather than counts: the same audit area (revenue, estimates, going concern, related parties) cited in consecutive inspections is more informative than a single finding. Ask the firm what it changed in response. Our inspection remediation page describes what that work typically involves.

Step 4: Check enforcement and disciplinary history

The PCAOB's Enforcement Actions page posts publicly available Board opinions, settled and litigated disciplinary orders, terminations of bars and related SEC and court actions. Sanctions can include revocation of a firm's registration, bars on individuals, censures and civil money penalties. Search for both the firm and the individual partners you will work with.

Keep one nuance in mind: if a respondent petitions the SEC for review, the PCAOB sanction is stayed and the Board cannot publicly report it until the stay is lifted. A clean search is a good sign, not a guarantee. It is also worth searching SEC litigation releases and administrative proceedings for the firm's name.

Step 5: Read the firm's Form 2 annual report

Every registered firm must file an annual report on Form 2 with the PCAOB by June 30. The PCAOB's registration and reporting resources describe it as providing basic information about the firm and its audit practice over the most recent 12-month reporting period. Firms also file special reports on Form 3 within 30 days of certain events, such as changes in name or certain legal proceedings.

Use these filings to check consistency: does the issuer client count in Form 2 match what the firm told you and what AuditorSearch shows? Has the firm filed Form 3 reports you should ask about?

Step 6: Search EDGAR for the firm's public clients

The SEC's EDGAR full-text search covers electronic filings since 2001 and lets you filter by form type and date. Searching the firm's exact name in quoted form, filtered to Form 10-K, 20-F, 1-K and 8-K, gives you a practical view of its issuer practice:

• 10-K and 20-F filings show the audit reports themselves, including any going-concern paragraphs and critical audit matters.
• Form 8-K Item 4.01 filings show where the firm was engaged, dismissed or resigned, whether any disagreements or reportable events were disclosed, and whether the former auditor's letter agreed with the company's statements. Frequent departures deserve a question. Our guide on how to change auditors explains what these filings contain.
• Late filings (NT 10-K) among the firm's clients can point to capacity problems in busy season.

Compare what you find with AuditorSearch. The two sources should tell the same story.

Questions to ask a prospective auditor

Public data narrows the list. The proposal meeting decides it. These are the questions we would ask in your position:

1. Independence. What independence checks do you perform before acceptance under SEC Rule 2-01 of Regulation S-X and PCAOB Rule 3520? PCAOB Rule 3526 requires the firm to describe to the audit committee, in writing and before accepting an initial engagement, relationships that may reasonably be thought to bear on independence. Ask for that communication, and confirm the fee arrangement is not contingent (PCAOB Rule 3521).
2. Capacity. How many issuer audits with the same year-end does the team carry? Who covers if a key person leaves in February?
3. Partner involvement. Who signs the report, and how involved will that partner be in planning, fieldwork and completion?
4. Engagement quality review. Who is the engagement quality reviewer under AS 1220, and when in the timeline is the review scheduled? The firm cannot let you use its report until the reviewer gives concurring approval, so a late review can delay a filing.
5. Other firms. Will any other accounting firm or offshore team perform part of the audit? Who, where, and what share of hours?
6. Industry and transaction experience. Has the team audited companies with your revenue model, your type of financing (convertible notes, warrants) or your planned transaction (reverse merger, uplisting, Reg A)?
7. Language and time zone. If your accounting team or operations are in Latin America, will the team work in Spanish as well as English, and in overlapping hours?
8. Fee and timeline. Is the fee fixed and in writing? What is the week-by-week timeline, and what triggers additional fees? See how we price for the factors we consider.

Red flags

• The firm cannot or will not give you its PCAOB Firm ID, or its registered name differs from the proposal without explanation.
• Registration revoked, pending withdrawal, or recent disciplinary orders involving the firm or the proposed partner.
• The same Part I.A themes repeated across inspections, or public Part II criticisms.
• Form AP data showing most of the work done by other firms that were not mentioned in the proposal.
• A long list of Item 4.01 resignations or many clients filing late.
• A fee far below the market with no written scope, or any fee tied to the outcome of a transaction.
• Promises that no one can make, such as "no comments from the SEC" or "a guaranteed filing date".
• No named engagement quality reviewer, or a partner who will only appear at sign-off.

If your current firm shows several of these signs, our change of auditor service explains how a transition works. If you are an OTC company comparing firms, see our PCAOB audits for OTC companies.

Sources

1. AuditorSearch — PCAOB
2. Registered Firms — PCAOB
3. Registration and Reporting Resources — PCAOB
4. Form AP, Auditor Reporting of Certain Audit Participants — PCAOB
5. Inspection Procedures — PCAOB
6. Basics of Inspections — PCAOB
7. Firm Inspection Reports — PCAOB
8. Enforcement Actions — PCAOB
9. PCAOB Rules, Section 3 (Rules 3211, 3520, 3521, 3526) — PCAOB
10. AS 1220, Engagement Quality Review — PCAOB
11. Quality Control implementation resources (QC 1000 status) — PCAOB
12. EDGAR Full Text Search — U.S. Securities and Exchange Commission
13. OTCQB Rules (V6, April 6, 2026) — OTC Markets Group
14. OTCQX Rules for U.S. Companies (V11, April 6, 2026) — OTC Markets Group