Audit
Learn what an audit is, the types, the process, and how to keep your records audit-ready.
Published Thursday 23 July 2026
Table of contents
Key takeaways
- An audit is an independent check of your financial records or operations, and it gives reasonable, not absolute, assurance that they're accurate.
- The main types you'll meet are tax audits from the Inland Revenue Department, external audits and internal audits, and each one serves a different purpose.
- Keeping organised records year round and meeting the 7-year retention rule makes any audit faster and less stressful.
- Not every small business in New Zealand has to be audited, so it pays to check what your structure, industry and investors or lenders require.
Audit definition
An audit is a detailed check of your business's financial records, tax returns or operations to confirm they're accurate and follow the rules. An audit gives reasonable, not absolute, assurance that your records are free from material error.
Most audits focus on financial and tax matters, and they usually review your financial records in detail. Audits can also examine other areas of your business, including:
- industry compliance: meeting sector-specific standards
- operational processes: internal procedures and controls
- statutory requirements: legal and regulatory obligations
Independent auditors usually carry out these checks to stay objective. In New Zealand, registered audit firms have a quality review at least every 4 years, so you can trust the standard of their work.
Types of audits
Three main audit types affect small businesses, and each one serves a different purpose. The clearest way to tell them apart is who runs them and why.
A tax audit is run by the Inland Revenue Department (IRD), which examines your tax returns for accuracy and compliance. During a tax audit, auditors will:
- review tax returns, profit and loss statements, and deductions
- select businesses at random or when returns show discrepancies
- request documentation to back up the details you've reported
An external audit is carried out by independent professionals who verify your financial records or operations from outside your business. In an external audit, auditors will:
- check for fraud and verify record accuracy, which matters for loans or investors
- check compliance with standards such as ISO, which can change over time
- stay objective by working as third parties with no stake in the results
An internal audit is run by your own team or an independent expert to review your internal processes. The key difference is direction: an external audit gives outsiders an unbiased view, while an internal audit helps you improve from within. An internal audit will:
- identify weaknesses in your business controls
- check compliance with your internal policies
- uncover opportunities to improve how you operate
An audit process
Most audits follow four main stages, whoever runs them. Knowing the stages helps you prepare the right records at the right time.
In the planning stage, auditors define the scope and get to know your business. At this stage they will:
- outline what records and processes the audit will cover
- learn about your industry and business operations
- set the timeline and requirements for the audit
During information gathering, auditors collect the documentation they need to form a view. At this stage they will:
- request financial records, tax returns and supporting documents
- interview business owners, managers or accountants
- review your internal processes and controls
In the evaluation stage, auditors analyse everything they've gathered. At this stage they will:
- compare your records with the relevant standards and rules
- identify any discrepancies or compliance issues
- test the accuracy of your financial data and processes
Finally, auditors write a report that sets out their findings and recommendations. This report might accept your tax returns as filed, suggest corrections, or give a formal opinion on the accuracy of your financial records.
Audit opinions and outcomes
When a financial audit ends, the auditor gives an opinion on how accurate your records are. There are 4 opinion types you might receive, from best to worst outcome:
- unqualified opinion: a clean result, meaning your records are accurate and follow the standards
- qualified opinion: mostly accurate, with one or more specific issues the auditor has flagged
- adverse opinion: your records are materially misstated and don't fairly reflect your position
- disclaimer of opinion: the auditor couldn't gather enough evidence to form a view
Importance of audits
Audits do more than tick a compliance box, and they can help your business grow. The main benefits fall into 3 areas.
The first is compliance assurance, which confirms your business meets its tax and legal obligations. An audit verifies accurate reporting to regulators and helps you correct any compliance gaps before penalties arise.
The second is error detection and correction, which protects the health of your finances. An audit can uncover:
- accounting errors: calculation mistakes and recording issues
- fraud: unauthorised transactions or financial manipulation
- process weaknesses: gaps in your financial controls
The third is business credibility and growth, which builds confidence with the people you rely on. Verified records help you:
- build trust with investors, lenders and suppliers
- get clear information to support your business decisions
- show you're committed to accurate financial reporting
Audit checklist
Good preparation makes any audit easier by keeping your records organised and ready for review. Work through these 3 steps to stay audit-ready.
First, maintain organised records so nothing goes missing. To keep your records in order:
- use tools like Hubdoc to digitise receipts and invoices automatically
- store financial documents in clearly labelled, accessible formats
- update your bookkeeping regularly throughout the year
Second, meet the record retention requirements that apply in New Zealand. According to the Inland Revenue Department, you need to keep these records for at least 7 years, and some situations call for longer, so check with the IRD if you're unsure.
Third, establish audit-ready processes so you're prepared before any audit begins. To build reliable processes:
- write clear policies for your financial and operational processes
- review your processes regularly to spot issues early
- work with qualified accountants and bookkeepers for compliance guidance
Who needs an audit in New Zealand?
Not all small businesses in New Zealand have to be audited. Whether you need one depends on your circumstances rather than a single blanket rule.
Your obligation usually comes down to your business structure, your industry, and whether investors, lenders or regulators require verified accounts. Some companies and not-for-profits must be audited by law, while many small businesses choose an audit to build trust or meet a lender's conditions. If you're not sure where you stand, check your requirements with your accountant or the relevant regulator.
Keep your records audit-ready with Xero
Xero helps you prepare for an audit by automating record keeping and keeping your financial data ready for review. Less manual admin means fewer errors and a smoother audit.
With automated record management, Xero helps you:
- match transactions automatically to reduce manual errors
- capture and store receipts with Hubdoc
- keep your financial records up to date without manual data entry
With audit-ready reporting, you can generate profit and loss statements, balance sheets and cash flow reports in a few clicks. You also get a complete audit trail for every financial activity, so you can keep your records audit-ready year round. Get one month free and spend less time on manual admin.
FAQs on audits
Here are answers to some frequently asked questions about audits from small business owners.
How long does a typical audit take?
The time an audit takes depends on your business size, the audit scope and how organised your records are. A simple audit can take a few days, while a complex one may run to weeks or months.
What happens if the auditor finds issues?
If an auditor finds errors, they'll list them in the final report and often suggest how to fix them. You can then discuss the findings and provide more information if needed.
Can I dispute audit findings if I disagree?
Yes, you can dispute an auditor's findings. A tax audit has a formal appeals process, while for other audits you can talk to the auditor and provide evidence to support your view.
Do all small businesses need regular audits?
No, not all small businesses need regular audits, as it depends on your industry, structure and whether investors or lenders ask for one. Even when it isn't required, an audit can give you useful insights and build trust.
How much does an audit typically cost?
The cost of an audit depends on your business size, industry and how organised your records are. Get quotes from a few accounting firms to find out what it might cost for your business.
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Disclaimer
This glossary is for small business owners. The definitions are written with their requirements in mind. More detailed definitions can be found in accounting textbooks or from an accounting professional. Xero does not provide accounting, tax, business or legal advice.