Should Nonprofits Still Change Audit Firms Every Five Years?

“Are we supposed to switch auditors at some point?”

It’s a fair question. Many board members have heard that changing auditors regularly is considered a best practice. The logic seems straightforward. A new firm brings fresh eyes, a new perspective, and potentially a better chance of identifying issues that may have been overlooked over time.

What surprises many nonprofit leaders is that the answer is not nearly as simple as “yes, every five years.”

In fact, much of the Canadian discussion around audit quality has moved away from the idea of mandatory audit firm rotation and toward a more nuanced approach focused on auditor performance, independence, and oversight. CPA Canada and the Canadian Public Accountability Board have examined the issue extensively and concluded that automatically changing audit firms may not improve audit quality and, in some cases, could actually reduce it.

Why Some Boards Consider Changing Audit Firms

The primary concern is independence.

An external audit is valuable because it provides an independent opinion on an organization’s financial statements. Stakeholders, funders, donors, regulators, and board members rely on the auditor’s ability to remain objective and to challenge management when necessary.

The concern is that when an audit firm has worked with the same organization for many years, familiarity can develop. Auditors become deeply familiar with staff, operations, systems, and historical decisions. Some regulators and governance experts have questioned whether long-standing relationships could make it more difficult for auditors to maintain the same level of professional skepticism.

This concern led to discussions around mandatory audit firm rotation in several jurisdictions and sparked broader conversations about how organizations should assess the independence of their auditors.

It’s easy to understand why this idea gained momentum. Fresh perspectives can be valuable, particularly when organizations are growing, changing, or facing increasingly complex financial reporting requirements.

What Gets Lost When You Change Audit Firms

The challenge is that fresh eyes are not the only factor that influences audit quality.

An experienced audit firm accumulates valuable institutional knowledge over time. They understand the organization’s history, funding structure, internal controls, restricted funds, significant accounting judgments, and prior audit findings. They know why certain decisions were made and where areas of risk have existed in previous years.

That knowledge does not transfer overnight.

When a nonprofit changes audit firms, the new auditor must spend considerable time learning the organization. Management often spends additional hours gathering historical information, explaining prior decisions, and helping the new engagement team understand the operational and financial realities of the organization.

CPA Canada’s review of auditor independence and audit quality identified this as a significant concern. The loss of institutional knowledge and the learning curve associated with a new audit firm were viewed as factors that could potentially reduce audit quality rather than enhance it.

For nonprofits with complex grant arrangements, restricted contributions, reserve funds, endowments, or multiple funding sources, that learning curve can be particularly significant.

The Real Question: Is Your Auditor Still Challenging You?

One of the most interesting conclusions from CPA Canada’s work is that audit quality is not determined solely by how long an audit firm has been engaged.

Instead, boards should be evaluating whether the auditor continues to demonstrate independence, objectivity, and professional skepticism. In practical terms, that means asking whether the auditor is still asking difficult questions, challenging assumptions, and providing meaningful insight rather than simply repeating the same process year after year.

An audit should not feel like a routine compliance exercise.

A strong auditor should be helping the board understand risks, highlighting areas that deserve attention, discussing internal controls, and raising concerns when necessary. If the audit process has become overly predictable or if management never feels challenged, that may be a more meaningful concern than the number of years the firm has been engaged.

Questions Every Board Should Be Asking

Rather than starting with the question, “How long have we had this audit firm?” boards may get better results by asking:

• Does our auditor demonstrate independence and professional skepticism?
• Are we receiving useful recommendations and observations?
• Does the engagement team understand our sector and emerging risks?
• Is communication clear, transparent, and timely?
• Do our auditors challenge management appropriately?
• Are we satisfied with the quality of the audit process?
• Has the engagement team evolved over time to bring new perspectives?

These are many of the same themes reflected in CPA Canada’s guidance for audit committees assessing external auditors. The emphasis is on evaluating the quality of the auditor’s work rather than focusing exclusively on tenure.

A Better Approach Than Automatic Auditor Rotation

Rather than requiring organizations to change audit firms after an arbitrary period, CPA Canada and CPAB recommended that audit committees conduct periodic comprehensive reviews of the external auditor, alongside annual assessments. These reviews are intended to evaluate audit quality, independence, communication, professional skepticism, and overall performance.

This approach recognizes that every organization is different.

For one nonprofit, a review may identify valid reasons to seek proposals from new audit firms. Perhaps the organization has outgrown its current auditor, needs specialized expertise, or is no longer satisfied with the quality of service being provided.

For another organization, the review may confirm that the current firm continues to provide excellent value, maintains independence, and brings meaningful insight through its understanding of the organization’s history and operations.

Either outcome can be the right decision when it is based on a thoughtful evaluation rather than an arbitrary timeline.

So, Should You Change Audit Firms Every Five Years?

Not necessarily.

There is no universal rule that says nonprofits should automatically replace their audit firms every five years. While independence remains a critical consideration, Canadian guidance increasingly recognizes that continuity and institutional knowledge also contribute to audit quality.

The better question is whether your current auditor continues to provide the independence, objectivity, expertise, and challenge that your organization needs.

If the answer is yes, a long-standing relationship may be an asset rather than a liability.

If the answer is no, then it may be time to explore other options.

Good governance is not about changing auditors because the calendar says so. It’s about making an informed decision based on audit quality, organizational needs, and the long-term interests of the nonprofit.