Taking a sick day is the easy part. Proving it is where most arguments start. Very few workplace disputes are about whether paid sick leave exists; they are about evidence: whether your employer can demand a medical certificate for a single day, whether a statutory declaration will do when you cannot get a doctor's appointment, whether a certificate from a pharmacist or physiotherapist counts, and how much your manager is entitled to be told about what is actually wrong with you. This guide sets out what the Fair Work Act 2009 actually requires, what the Fair Work Ombudsman says an employer can and cannot ask for, and what happens if you refuse. For the entitlement itself (how many days you get and how it accrues) see personal leave versus sick leave and carer's leave.
Key takeaways
- One test governs everything: section 107 of the Fair Work Act says that if the employer requires it, you must give "evidence that would satisfy a reasonable person" that the leave was taken for a qualifying reason.
- There is no minimum absence before evidence can be demanded. The Fair Work Ombudsman states employers can ask for as little as 1 day or less off work.
- The Act names no document and no profession. A medical certificate and a statutory declaration are both examples of acceptable evidence, not legal requirements, and the evidence has to establish the reason for the leave rather than your diagnosis.
- If evidence is reasonably required and you give none, section 107(4) means you are not entitled to the leave, so the absence can be unpaid. Awards and enterprise agreements can add their own evidence rules on top.
The only test that matters: evidence that would satisfy a reasonable person
Sick leave and carer's leave sit in Division 7 of Part 2-2 of the Fair Work Act, the part of the Act that contains the National Employment Standards. Division 7 imposes two separate obligations on the employee, and they happen in order.
First, notice.You must tell your employer you are taking the leave. The notice must be given "as soon as practicable", which the Act expressly says "may be a time after the leave has started", and it must tell the employer the period, or expected period, of the leave. That is all. You do not need permission, and you do not have to explain yourself at that point.
Second, evidence, but only if the employer requires it. An employee who has given notice must, if required by the employer, give the employer evidence that would satisfy a reasonable person that the leave was taken for a qualifying reason. Note what the test is measuring. It is not measuring whether the document is a particular form, or whether it came from a particular kind of clinic. It is measuring whether the evidence establishes the reason for the absence.
Fair Work Act 2009 (Cth) s.107, headed "Notice and evidence requirements". Section 107(2) requires notice "as soon as practicable (which may be a time after the leave has started)" advising "the period, or expected period, of the leave". Section 107(3) requires the employee, "if required by the employer", to "give the employer evidence that would satisfy a reasonable person that ... if it is paid personal/carer's leave: the leave is taken for a reason specified in section 97". The Fair Work Ombudsman summarises the same rule.
The qualifying reasons come from section 97: that you are "not fit for work because of a personal illness, or personal injury" affecting you, or that you are providing care or support to a member of your immediate family or household who needs it because of their illness, their injury, or an unexpected emergency affecting them. Your evidence has to point at one of those reasons. Background on how the Act fits together is in our Fair Work Act guide.
When your employer can ask, and what they can ask for
Section 107(3) contains no timing rule and no threshold. The obligation is triggered by three words: "if required by the employer". In practice that means a request can arrive while you are still away, when you return, or later when payroll is being processed. There is no rule that the employer has to warn you in advance that evidence will be needed, although a sensible policy will say so.
Two things do limit the request. First, the Fair Work Ombudsman states that "the type of evidence requested must always be reasonable in the circumstances". Second, an award or registered agreement can specify when evidence has to be given and what type it has to be, which cuts both ways: it can make the rules stricter, or it can lock in a more generous option such as a statutory declaration.
A related trap is the pre-booked appointment. Medical appointments and elective surgery that are arranged in advance are only covered by sick leave if you are actually not able to work because of a personal illness or injury, and it depends on the individual circumstances. Your employer can ask for evidence confirming you were unfit for work, which then decides whether the day is paid as sick leave or has to come out of annual leave or unpaid leave.
Fair Work Ombudsman, Notice and medical certificates: "An award or registered agreement can specify when an employee has to give evidence to their employer and what type of evidence they have to give. The type of evidence requested must always be reasonable in the circumstances." The same page confirms pre-arranged appointments and elective surgery "can only be covered by sick leave if an employee is not able to work because of a personal illness or injury".
Can they really ask for a certificate for one day off?
Yes. This is the single most searched question about sick leave in Australia, and the answer surprises people. The Fair Work Ombudsman puts it plainly: "Employers can ask employees to provide evidence for as little as 1 day or less off work." Not three days. Not two. One day, or a partial day.
The widely believed "three day rule" does not exist in the Fair Work Act. Where a workplace genuinely operates on a rule like that, it comes from a workplace policy, an award or an enterprise agreement, and it is a concession by that employer rather than a floor set by law. An employer who has never asked for a certificate before is entitled to start asking, provided the request is reasonable in the circumstances. Equally, a policy that says "certificate required for every absence" does not create a new legal test: it is still section 107(3) that decides whether what you hand over is enough.
Fair Work Ombudsman, Notice and medical certificates: "Employers can ask employees to provide evidence for as little as 1 day or less off work." Nothing in section 107 sets a minimum period of absence before evidence can be required.
Who can issue a medical certificate
Here is the part most workplace policies get wrong. Section 107 does not use a defined form of document at all. It does not say "medical certificate", it does not name a profession, and it does not require a doctor. It requires evidence that would satisfy a reasonable person. The Fair Work Ombudsman describes medical certificates and statutory declarations as examplesof acceptable evidence and states that "there are no strict rules on what type of evidence needs to be given".
The practical consequence is that a certificate from a registered health practitioner other than a GP can satisfy the test, provided the condition falls within that practitioner's area of practice. A dentist certifying that you were unfit for work after oral surgery, a physiotherapist certifying a back injury they are treating, a psychologist, an optometrist, an osteopath or a chiropractor can all produce evidence that points at the section 97 reason. Pharmacists commonly issue what is usually called an absence from work certificate for short, minor illnesses. None of these is guaranteed to be accepted, because the reasonable person test still has to be met and because an award, agreement or policy may have specified something narrower, but a blanket refusal to accept any certificate not written by a doctor is not something section 107 supports.
Some awards recognise other practitioners explicitly. The Health Professionals, Medical Scientists and Support Services (Victoria) State Reference Public Sector Modern Award 2018, for example, deals separately with absences to attend a "chiropodist/podiatrist, chiropractor, dentist, optometrist, osteopath, physiotherapist or psychologist", and its evidence clause accepts certification by "a registered medical practitioner or health practitioner approved by the employer". Section 107 also says nothing about how the consultation took place, so a certificate issued after a telehealth appointment is not excluded by the Act; what matters is whether it would satisfy a reasonable person that you were unfit for work.
| Type of evidence | What it needs to establish | Typically used for | Limits to watch |
|---|---|---|---|
| Medical certificate from a GP | That you were not fit for work on the stated dates because of illness or injury | Any absence, short or long | The safest option, but the Act does not make it compulsory |
| Certificate from another registered health practitioner (dentist, physiotherapist, psychologist, optometrist, osteopath, chiropractor) | The same, within that practitioner's area of practice | Absences directly related to the condition they treat | An award, agreement or policy may name who is accepted |
| Pharmacist absence from work certificate | That a short, minor illness prevented you working | One or two days for a cold, gastro or similar | Not designed for long or serious absences; some employers push back |
| Statutory declaration | A formal declaration of the facts of your illness or caring responsibility | When a certificate cannot be obtained in time | Awards or agreements may cap how often it can be used |
| Hospital or emergency department paperwork | Attendance and dates, and often unfitness for work | Sudden or serious illness or injury | May show attendance without stating you were unfit for work |
| Certificate or letter about a family or household member | That the member required care or support because of illness or injury | Paid and unpaid carer's leave | Usually issued to the patient, so you may need their consent |
| Evidence of an unexpected emergency (school or childcare notice, incident report) | That an unexpected emergency affected the family or household member | Carer's leave only | Emergencies are not limited to illness or injury |
Most modern awards add nothing at all and simply hand the question back to the NES. The Building and Construction General On-site Award 2020, for instance, says only that "Personal/carer's leave entitlements are provided for in the NES". Stricter or more generous evidence clauses are far more common in enterprise agreements and in industry-specific or public sector awards, so it is always worth reading your own instrument. Find yours through our awards section and see how award terms interact with the NES in our modern awards guide.
Fair Work Ombudsman: "Medical certificates or statutory declarations are examples of acceptable forms of evidence. While there are no strict rules on what type of evidence needs to be given, the evidence has to convince a reasonable person that the employee was genuinely entitled to the sick or carer's leave." Award examples: MA000157 clauses 27.6 and 27.7, and MA000020 clause 32.1. Section 107(5) is the provision that lets a modern award or enterprise agreement "include terms relating to the kind of evidence that an employee must provide".
Is a statutory declaration acceptable instead of a medical certificate?
In most cases, yes. The Fair Work Ombudsman lists a statutory declaration alongside a medical certificate as an example of acceptable evidence, and its own published example is squarely on this point: an employee whose workplace required a medical certificate for Monday absences could not get a doctor's appointment, provided a statutory declaration when she returned on the Tuesday, and was paid for her day off. A workplace policy demanding a certificate does not automatically defeat a statutory declaration, because the statutory question is whether the evidence would satisfy a reasonable person.
A statutory declaration is not a note you scribble out. A Commonwealth statutory declaration is made under the Statutory Declarations Act 1959, which requires either that you sign it in the approved form while observed by a prescribed person (in person or by video link), or that it is made by digital verification. Because you are formally declaring the facts to be true, the declaration should state plainly what happened: the dates you were absent, that you were unfit for work because of a personal illness or injury, or the caring responsibility that kept you away, and why you could not obtain a certificate.
The limits are worth knowing. An award or enterprise agreement can cap how often a statutory declaration will be accepted. The Victorian health sector award mentioned above, for example, accepts a statutory declaration "with respect to absences on three occasions in any one year", with each occasion not exceeding three consecutive working days. Outside a term like that, repeatedly using declarations in place of certificates makes it easier for an employer to argue a reasonable person would want more.
Fair Work Ombudsman, Notice and medical certificates, worked example: "Anna gave her employer a statutory declaration when she came back to work on Tuesday because she couldn't get an appointment to see a doctor to ask for a medical certificate. She was paid for her day off." Formal requirements: Statutory Declarations Act 1959 (Cth) s.8, which requires a declaration to satisfy either s.9 (observation by a prescribed person, in person or by video link) or s.9A (digital verification).
What your employer is, and is not, entitled to know
This is the point people in a dispute most often get wrong, in both directions. Read section 107(3) closely: the evidence must satisfy a reasonable person that the leave "is taken for a reason specified in section 97". For your own sick leave, the section 97 reason is that you were not fit for work because of a personal illness or personal injury. The statutory question is your fitness for work, not the name of your condition. Nothing in the section requires the certificate to state a diagnosis, and a certificate that says an employee was seen on a date and was unfit for work over stated dates addresses exactly what the section asks.
The Act flags the privacy dimension itself. The note at the end of section 107 says that "personal information given to an employer under this section may be regulated under the Privacy Act 1988". Health information is treated as sensitive personal information, and the Fair Work Ombudsman's workplace privacy guidance notes that the Privacy Act sets higher standards for collecting and handling it, while also warning employers that it is generally not appropriate to disclose an employee's medical history. Note the wrinkle: personal information an employer holds about a current or former employee, used directly in relation to their employment, sits outside the Australian Privacy Principles, so the practical protection often comes from the employer's own policies and from the limits on what can reasonably be demanded rather than from a direct right to sue.
Two things the Fair Work Ombudsman says are not reasonable are worth quoting to a manager who pushes too far: an employer attending your medical appointment (unless you ask them to), and an employer contacting your doctor for further information. If you are asked to disclose a diagnosis you do not want to share, the constructive response is to offer evidence that goes to unfitness for work instead, and to ask which award, agreement or policy term the request is based on.
Fair Work Act 2009 (Cth) s.107 note: "Personal information given to an employer under this section may be regulated under the Privacy Act 1988." Fair Work Ombudsman: "We don't consider it reasonable for an employer to go to a medical appointment with an employee unless an employee requests this. We also don't consider it reasonable for an employer to contact the employee's doctor for further information." See also the Workplace privacy best practice guide on sensitive personal information and the employee records position.
Evidence for carer's leave is about someone else
Carer's leave changes what the evidence has to prove. For paid carer's leave, section 107(3)(a) still points to section 97, but the relevant limb is that a member of your immediate family or household required care or support because of a personal illness, a personal injury, or an unexpected emergency affecting them. For unpaidcarer's leave, section 107(3)(b) points instead to a permissible occasion in the circumstances specified in section 103(1). Either way, the document usually needs to be about the person you were caring for, not about you.
That creates a practical problem: a certificate for a sick child or partner is issued to them, so you may need their consent to hand it over, and for a household member who is not a relative that can be awkward. A statutory declaration from you describing the illness and the care you provided is often the cleaner route, and it is expressly one of the acceptable forms of evidence.
Unexpected emergencies are a category of their own. They are not limited to illness or injury, so there may be no certificate in existence at all. The Fair Work Ombudsman's published example is a parent who takes carer's leave to collect a child from school when the usual arrangement falls through. Evidence there might be a message from the school, an incident report, or a declaration setting out what happened. Do not confuse any of this with compassionate and bereavement leave or family and domestic violence leave, which are separate entitlements with their own rules.
Casual employees are not exempt.Casuals do not accrue paid personal/carer's leave, but every employee including a casual is entitled to 2 days of unpaid carer's leave per occasion, and section 107 applies to that leave in exactly the same way. A casual who is asked for evidence and provides none is in the same position as anyone else. Full-time and part-time employees can only use unpaid carer's leave once their paid balance is gone, because section 103(3) says unpaid carer's leave cannot be taken during a period when paid personal/carer's leave could be taken instead.
Fair Work Act 2009 (Cth) s.97 sets the qualifying reasons, and s.103 governs unpaid carer's leave, including s.103(3): an employee "cannot take unpaid carer's leave during a particular period if the employee could instead take paid personal/carer's leave". The Fair Work Ombudsman confirms all employees including casuals get 2 days per occasion, and its library article on carer's leave and unexpected emergencies confirms emergencies "aren't limited to illnesses or injuries".
Use the personal and carer's leave calculator to work out your accrued balance in hours and days.
What happens if you refuse, or your evidence is rejected
The consequence is written into the Act, and it is blunt. Section 107(4) provides that an employee "is not entitled to take leave under this Division unless the employee complies with this section". If evidence was properly required and you provide none, the entitlement does not arise, which is why the Fair Work Ombudsman says an employee who does not give evidence when asked "may not be entitled to be paid for their sick or carer's leave". The day is then usually treated as unauthorised and unpaid, and a repeated pattern can be handled by the employer as a conduct or performance matter.
There are three limits on that, and they matter if you are already in a dispute.
- The requirement must be reasonable. The Fair Work Ombudsman is explicit that the type of evidence requested must always be reasonable in the circumstances, so an unreasonable demand is a weak foundation for docking pay.
- Compliance is judged against the statutory test, not the wording of the request. If you hand over something that would satisfy a reasonable person, you have complied with section 107(3) even if it is not the exact document the policy named. That is precisely the situation in the Fair Work Ombudsman's statutory declaration example.
- Taking leave you are entitled to is a workplace right. Adverse action includes injuring an employee in their employment, which expressly covers not giving an employee their legal entitlements such as pay or leave. Action taken because you used or proposed to use a workplace right can found a general protections claim, and a dismissal may also be challengeable as an unfair dismissal. Time limits are short: 21 days from the day after dismissal for a dismissal-related application to the Fair Work Commission.
If you are told a certificate has been rejected, ask in writing which term of the award, enterprise agreement or policy the employer is relying on, and keep a copy of everything you provided and when. Definitions of the terms used in that correspondence are in our glossary.
Fair Work Act 2009 (Cth) s.107(4): "An employee is not entitled to take leave under this Division unless the employee complies with this section." Fair Work Ombudsman: "An employee who doesn't give their employer evidence when asked may not be entitled to be paid for their sick or carer's leave." On adverse action and the 21-day limit, see the Fair Work Ombudsman's Protections at work page.
A worked example
Marcus is a full-time warehouse employee covered by an award that says only that personal/carer's leave is provided for in the NES. His employer's policy states that a medical certificate is required for any absence adjoining a weekend or public holiday. He wakes on the Monday of a long weekend with gastro, phones his supervisor at 6am to say he cannot work and expects to be off for the day, and cannot get a same-day appointment anywhere.
Notice. Marcus met section 107(1) and (2) with the 6am call: it was as soon as practicable and it advised the expected period of leave. He did not need to give a diagnosis to do that.
Evidence. His employer requires evidence, as it is entitled to do for a single day. Marcus visits a pharmacy that afternoon and obtains an absence from work certificate for that day, and also makes a Commonwealth statutory declaration setting out the dates, that he was unfit for work because of a personal illness, and that no appointment was available.
Outcome. Between them, those documents would satisfy a reasonable person that the leave was taken for a section 97 reason, so section 107(3) is met and the day is payable as paid personal/carer's leave. The policy asked for a doctor's certificate, but the policy is not the legal test. Compare the Fair Work Ombudsman's own example, where a statutory declaration was accepted for exactly this reason and the employee was paid.
If the employer still refuses, Marcus should ask in writing which term of the award or agreement makes his evidence insufficient. Withholding payment for leave he is entitled to is capable of amounting to adverse action.
Frequently asked questions
Can my employer ask for a medical certificate for a single day off?
Yes. The Fair Work Ombudsman states that employers can ask employees to provide evidence for as little as 1 day or less off work. There is no minimum period of absence in section 107 of the Fair Work Act before evidence can be required, and the "three day rule" many people believe in comes from workplace policies, not from the legislation.
Will a statutory declaration be accepted instead of a medical certificate?
Usually. The Fair Work Ombudsman names statutory declarations as an example of acceptable evidence, and its published example has a statutory declaration accepted, and the employee paid, where a doctor's appointment could not be obtained. The exception is where an award or enterprise agreement sets specific evidence terms, which can limit how often a declaration can be used.
Can a pharmacist or physiotherapist write my certificate?
Section 107 does not name any profession. It asks only for evidence that would satisfy a reasonable person that the leave was taken for a qualifying reason, and the Fair Work Ombudsman confirms there are no strict rules on the type of evidence. A certificate from a registered health practitioner other than a doctor can meet that test where the condition is within their area of practice, though an award, agreement or policy may specify who it accepts.
Does my medical certificate have to say what is wrong with me?
No. The evidence has to establish the reason for the leave, which for your own sick leave is that you were not fit for work because of a personal illness or injury. Section 107 does not require a diagnosis, and the Act itself notes that personal information given to an employer under the section may be regulated by the Privacy Act 1988.
Can my employer ring my doctor to check?
The Fair Work Ombudsman says it does not consider it reasonable for an employer to contact an employee's doctor for further information, or to attend a medical appointment with an employee unless the employee asks them to.
What evidence do I need for carer's leave?
Evidence that would satisfy a reasonable person that an immediate family or household member required care or support because of illness, injury or an unexpected emergency. That may be a certificate issued to the person you cared for, or a statutory declaration from you. Because emergencies are not limited to illness or injury, there may be no certificate at all, and a school or childcare notice can be the relevant proof.
What happens if I do not provide evidence when asked?
Section 107(4) means you are not entitled to take the leave unless you comply, so the absence can be unpaid and may be treated as unauthorised. If the request was unreasonable, or if you did provide evidence that would satisfy a reasonable person, you have a basis to dispute the decision. More common questions are answered in our FAQ.
Do casual employees have to provide evidence?
Yes. Casuals do not accrue paid sick leave, but they are entitled to 2 days of unpaid carer's leave per occasion, and the notice and evidence rules in section 107 apply to that leave in the same way.
Author & reviewer
Sarah has spent over a decade advising Australian SMBs on Fair Work, NES compliance, and payroll. Based in Sydney, she has worked across hospitality, retail and professional services.