When an employee calls in sick, an Australian employer is allowed to ask for proof. What that proof has to look like, when an employer can ask for it, and what employers can and cannot do with the health information they receive is governed mostly by the Fair Work Act 2009 (Cth) and the National Employment Standards (NES) sitting inside it.
The concept itself is narrower than most workplaces assume. There is no statutory list of acceptable certificates, no minimum number of days before evidence can be requested, and no fixed format. Instead, the Act sets a single test — the evidence must "satisfy a reasonable person" that the employee was genuinely entitled to the leave. This article works through:
- The statutory framework for personal/carer's leave evidence
- What counts as evidence that would satisfy a reasonable person
- When an employer can ask for it, and how the request has to be made
- Privacy limits on what the employer can ask about
- How the rules differ for casual employees
- A worked example of a typical absence
- Where legal advice usually adds value
The statutory framework
The NES gives full-time and part-time employees 10 days of paid personal/carer's leave a year, accruing progressively and rolling over year to year. "Personal/carer's leave" is the umbrella — it covers the employee's own illness or injury and care or support for an immediate family or household member.
The conditions on taking that leave sit in s 107 of the Fair Work Act 2009 (Cth), titled "Notice and evidence requirements". Two obligations matter here:
- Notice. The employee must tell the employer as soon as practicable (which may be after the leave has started) and tell them how long the absence is expected to last.
- Evidence. If the employer asks, the employee must provide evidence "that would satisfy a reasonable person" that the leave is being taken for a permitted reason.
The Act doesn't prescribe a form. It doesn't say the evidence has to be a medical certificate. It says the evidence has to do a job — convince a reasonable person the absence was genuine.
What counts as evidence that would satisfy a reasonable person
The two most common forms are:
- A medical certificate from a registered health practitioner (most commonly a GP).
- A statutory declaration sworn by the employee, used where a medical appointment was not reasonably available, or for short absences.
Other documents can satisfy the test in the right circumstances — a hospital discharge summary, an emergency department record, or written confirmation from a treating practitioner. The Fair Work Ombudsman's guidance on notice and medical certificates confirms there are no strict rules on what type of evidence is required; the evidence simply has to convince a reasonable person the entitlement was genuine.
Whether a particular document is enough is judged in context. A statutory declaration covering a single day of gastro after the employee couldn't get a same-day GP appointment is probably reasonable. A statutory declaration covering a fortnight of unexplained absence probably isn't.
When an employer can ask, and how to ask
An employer can ask for evidence for any period of personal/carer's leave — there is no minimum trigger of "two days or more" written into the Act. What the Act requires is that the request itself be reasonable.
Reasonable practice tends to include:
- A written policy stating when evidence will be required (every absence, after a single day, or only for patterns) and accepted forms.
- Consistent application across staff, so the same standard applies to a casual barista as to a salaried manager.
- Proportionality. A single day's absence with clear symptoms often calls for less than a week off work.
- Discretion for emergencies — where the employee genuinely could not get a medical appointment, a statutory declaration is the usual fallback.
What is not reasonable, on the Fair Work Ombudsman's own guidance, is the employer attending a medical appointment with the employee, or contacting the employee's doctor directly for more information. Those steps cross from verifying entitlement into investigating private medical affairs.
Privacy limits on what the employer can ask
The evidence rule asks only that the employer be satisfied the leave was genuinely taken for personal illness, injury, or to care for an immediate family or household member. It does not entitle the employer to a diagnosis.
In practice, that means an employer can ask for confirmation of two things:
- The employee was unfit for work (or needed to provide care, for carer's leave).
- The expected duration of the absence.
Asking for the diagnosis, the treating practitioner's clinical notes, or details of medication is generally a step beyond what the entitlement allows. There are narrow exceptions — for example, where a safety-critical role requires confirmation the employee can perform the inherent requirements without risk, or where reasonable adjustments need to be scoped. Even then, the question is about capacity for work, not about the medical condition itself.
Medical evidence collected from employees is sensitive information under the Privacy Act 1988 (Cth) where the employer is APP-covered, and even where the small-business exemption applies, the duty of care and trust-and-confidence implications of mishandling health information are real. Store it securely, limit access, and don't share it beyond the people who need to know.
How the rules change for casual employees
Casuals do not receive paid personal/carer's leave. They do, however, get 2 days of unpaid carer's leave per occasion when an immediate family or household member needs care because of illness, injury, or unexpected emergency. That entitlement applies to all employees, casuals included.
For a casual's own illness, the practical question is usually about the rostered shift rather than paid leave — the casual is declining or unable to work the shift, and the employer needs to know whether to backfill. An employer can still ask for reasonable evidence to support unpaid carer's leave, and a written policy on shift-cancellation notice and acceptable evidence helps everyone know where they stand.
A worked example
Consider Priya, a full-time accounts coordinator at a mid-sized logistics firm. The firm's leave policy requires a medical certificate for any absence of two consecutive days or longer, and a statutory declaration is accepted for single days where a GP appointment couldn't be obtained.
Priya wakes up on a Monday with a heavy cold. She texts her manager before 8 am — that meets the "as soon as practicable" notice obligation in s 107 — and says she expects to be back Wednesday.
When she calls a GP at 8.30 am the surgery is booked out for two days. Priya sees a pharmacist, gets over-the-counter advice, and rests. On Tuesday morning she gets a telehealth appointment and a medical certificate covering Monday and Tuesday. She returns Wednesday and emails the certificate to her manager.
The firm has what it needs. The certificate is from a registered medical practitioner and covers the period claimed. The diagnosis isn't on the certificate and the firm doesn't ask for it. The leave is paid against Priya's accrued personal leave balance. The certificate is filed in the secure HR folder with access limited to the HR lead and Priya's direct manager.
Compare a different employee, Jordan, who is absent on the Monday after a long weekend for the third time in three months, with no certificates and no statutory declarations. Jordan's pattern is the kind of situation where the employer can fairly tighten the evidence requirement going forward — by writing to Jordan, explaining the concern about pattern attendance, and confirming that evidence will be required for any future absence. That step focuses on conduct and process, not on the medical question, and applies the policy consistently.
When Artificer Legal can help
Most of the friction in sick-certificate disputes comes from documents that haven't kept pace with how the business actually runs — a 2018 employment contract sitting under a 2024 leave policy, or a policy that says one thing and a manager doing another. The legal work that helps most is preventative:
- Reviewing and aligning the leave policy so the trigger for evidence, accepted forms, and consequences of non-compliance are written down and consistent.
- Updating employment contracts so notice and evidence expectations match the policy and the contract supports the policy if it is challenged.
- Drafting manager scripts and checklists for handling sick calls — what to say, what to record, what not to ask.
- Advising on individual cases where the situation is sensitive: repeated short absences, suspected misuse, long-term illness, fitness-for-duty assessments, or where termination on capacity grounds is being considered.
The last category is where the cost of getting it wrong climbs sharply. Termination linked to illness or disability sits at the intersection of the Fair Work Act 2009 (Cth) general protections, unfair dismissal, and federal and state anti-discrimination law. Early advice is materially cheaper than a defended claim.
If you're refreshing your leave policy, updating contracts, or working through a difficult attendance case, Artificer Legal can help you scope the work and the documents you actually need.
In short
The Fair Work Act gives employers a clear right to ask for reasonable evidence of personal/carer's leave, and gives employees a clear right to privacy about the underlying condition. The line between the two is the "reasonable person" test in s 107.
In practice, that means a written leave policy that sets the trigger and accepted forms of evidence, consistent application across the team, proportionate requests tied to the length and pattern of absence, limits on the health information collected to capacity and expected duration, and a slightly different overlay for casuals — no paid personal leave, but a shared 2-day unpaid carer's leave entitlement and a fair set of expectations about shift cancellation. Get those settings written down once, train managers to apply them the same way each time, and most sick-certificate questions answer themselves.