Compliance Management, Audit and Due Diligence · Audit Principles and Techniques

Audit Evidence and Documentation: SA 500 Explained

Updated 11 October 2026 · Fact-checked

Audit evidence is the information the auditor uses to support the opinion. Under SA 500 it must be sufficient (enough quantity) and appropriate (relevant and reliable). You get it by inspection, observation, confirmation, recalculation, reperformance, analytical procedures and inquiry, and you record the work in audit documentation.

Understand Audit Evidence and Documentation

Audit evidence is the information the auditor uses to reach conclusions on which the opinion is based. It includes the accounting records and other information from inside and outside the entity. It also includes information that contradicts management's assertions. Even the absence of information, such as management refusing a requested representation, can be audit evidence.

Two words decide everything: sufficient and appropriate. Sufficiency measures the quantity of evidence. Appropriateness measures quality, that is, its relevance and reliability. The two are interrelated. Higher assessed risk of misstatement means more evidence is likely needed. Higher quality means less may be needed. But more evidence may not make up for poor quality.

Reliability depends on the source and nature of the evidence and the circumstances in which it was obtained. Whether you have enough is a matter of professional judgment. The aim is to reduce audit risk to an acceptably low level, so that you can draw reasonable conclusions.

SA 500 requires you to design and perform procedures that are appropriate in the circumstances. Inquiry alone ordinarily does not give sufficient evidence that there is no material misstatement at the assertion level, or that controls operate effectively. You need to combine it with other procedures.

Audit documentation (SA 230) is the written record of what you did, what evidence you got and what you concluded. It supports the report and shows that the audit followed the standards. Evidence is cumulative: you build it across the audit and record it in the working papers.

Key rules to remember

Sufficient appropriate audit evidence: Sufficient appropriate = Sufficiency (quantity) + Appropriateness (relevance + reliability); Required to reduce audit risk to an acceptably low level (SA 200, para 17).
Risk and quantity: Higher assessed risk → more evidence; higher quality → less evidence; More evidence may not compensate for poor quality (SA 500, A4).
Audit procedures to obtain evidence: Inspection, observation, confirmation, recalculation, reperformance, analytical procedures, inquiry; Often used in combination. Inquiry alone is ordinarily not enough (SA 500, A2).
If evidence is insufficient: Obtain further evidence via other SAs, or extend work, or perform other necessary procedures; else assess effect on report; Based on SA 200, A71.

How to solve Audit Evidence and Documentation questions

Use this method for any written question on audit evidence or documentation.

1Identify what is asked: meaning, procedures, sufficiency or appropriateness, or a case about a specific assertion.
2State the rule briefly: evidence must be sufficient and appropriate, and its sufficiency is a matter of professional judgment.
3Define sufficiency as quantity and appropriateness as relevance plus reliability.
4Link the facts to risk: higher risk needs more evidence; poor quality is not cured by quantity.
5Name the procedures suited to the facts, such as confirmation for debtors or inspection for assets, and note that inquiry alone is not enough.
6Decide whether the evidence is enough. If not, say what the auditor should do: extend work, perform other procedures, or consider the effect on the report.
7Mention documentation: record the work, evidence and conclusions in the working papers.
8Close with a one-line conclusion.

Quickest way: S-A-P-D check

When to use it: When time is short and the question gives a short fact situation.

S: Is the evidence sufficient, meaning enough in quantity for the assessed risk?
A: Is it appropriate, meaning relevant and reliable given its source and nature?
P: Which procedure fits, and is inquiry being used alone?
D: Is the work and conclusion documented in the working papers?
Write your conclusion and the next step the auditor should take.

Common mistakes in Audit Evidence and Documentation

Treating sufficiency and appropriateness as the same thing.
Both words sound like 'enough'.
Fix: Sufficiency is quantity. Appropriateness is quality (relevance and reliability). Write both definitions.
Saying more evidence cures weak evidence.
Students assume volume equals assurance.
Fix: State that obtaining more audit evidence may not compensate for its poor quality.
Relying on inquiry alone as proof.
Management answers feel convincing.
Fix: Say inquiry alone ordinarily does not give sufficient evidence of no material misstatement or of operating effectiveness of controls. Corroborate it.
Listing only documents as audit evidence.
Vouching is the most familiar technique.
Fix: Include observation, confirmation, recalculation, reperformance and analytical procedures. Also note that contradictory information and absence of information can be evidence.
Giving a fixed amount of evidence needed.
Students want a rule of thumb.
Fix: Say it is a matter of professional judgment, driven by risk and quality.
Ignoring documentation in the answer.
The question seems to ask only about evidence.
Fix: Add a line that the procedures, evidence and conclusions are recorded in working papers.

Worked examples

Example 1

Explain what is meant by 'sufficient appropriate audit evidence'. Can an auditor offset poor-quality evidence by collecting more of it?

Show the solution

Audit evidence is the information used by the auditor to reach conclusions on which the opinion is based.
Sufficiency is the measure of the quantity of evidence. It is affected by the assessed risks of misstatement: the higher the risk, the more evidence is likely to be required.
Appropriateness is the measure of quality, that is, relevance and reliability. Reliability is influenced by source, nature and the circumstances in which the evidence is obtained.
The two are interrelated. Higher quality may reduce the quantity needed.
However, obtaining more audit evidence may not compensate for its poor quality.

Answer: Sufficient appropriate evidence is enough quantity of relevant, reliable evidence to reduce audit risk to an acceptably low level. No, more evidence of poor quality does not offset its poor quality.

Example 2

While auditing Sharma Traders Ltd., the auditor asks the accounts manager whether all stock is intact. The manager says yes. The auditor records this and moves on. Comment.

Show the solution

Inquiry is a valid procedure and can give important evidence.
But inquiry alone ordinarily does not provide sufficient evidence of the absence of a material misstatement at the assertion level.
The auditor should corroborate through other procedures, for example observing the physical stock count, inspecting stock records, and recalculating valuation.
If the evidence remains insufficient, the auditor should extend the work or perform other necessary procedures, and consider the effect on the report if evidence cannot be obtained.
The auditor should record the procedures, evidence and conclusions in the working papers.

Answer: The auditor's approach is inadequate. The manager's reply must be corroborated by other procedures, and the whole work documented.

Exam tips

Define sufficiency and appropriateness in separate lines. Examiners look for both definitions.
In case questions, tie the amount of evidence to risk and its quality to source and nature.
List procedures with a one-line use for each rather than just names.
Add a documentation sentence to every answer on this topic.
For vouching versus verification, state clearly that vouching checks transactions to supporting documents, while verification checks existence, ownership and valuation of assets and liabilities.

Practice questions from Audit Principles and Techniques

Audit Evidence and Documentation in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Audit Evidence and Documentation: frequently asked questions

What does sufficient appropriate audit evidence mean under SA 500?

Sufficient means enough quantity. Appropriate means good quality, that is, relevant and reliable. Together they allow the auditor to reduce audit risk to an acceptably low level and draw reasonable conclusions.

What procedures are used to obtain audit evidence?

Inspection, observation, confirmation, recalculation, reperformance and analytical procedures, often in combination, along with inquiry. Inquiry alone ordinarily is not enough.

What is the difference between vouching and verification?

Vouching examines recorded transactions against supporting documents to confirm they are authentic and properly recorded. Verification confirms the existence, ownership, valuation and presentation of assets and liabilities.

Why is audit documentation needed?

It records the work done, the evidence obtained and the conclusions reached. It supports the auditor's report and shows the audit was performed in line with the standards.