Good reasons for sick leave and what the law requires of Australian employers

An employee calls in sick at 7am on a Monday. By the end of the day you have made three decisions: whether the absence is a legitimate use of personal/carer's leave, whether you can ask for a medical certificate, and how the absence should be recorded. Get any of them wrong and the business is exposed to a Fair Work Ombudsman investigation, a general protections claim, or an unfair dismissal application.

The underlying obligation is easy to state and harder to administer. Personal/carer's leave is part of the National Employment Standards (the NES) in the Fair Work Act 2009 (Cth), and every employer in the national workplace relations system must give it when a qualifying reason exists, pay it correctly, and only ask for notice and evidence within the limits the Act sets. This guide sets out who those rules apply to, what counts as a good reason for sick leave, your notice and evidence duties, what happens when a leave balance runs out, and the consequences of getting it wrong.

Who the sick leave rules apply to

The NES applies to all employees covered by the national workplace relations system, which in practice means employees of private sector businesses across Australia. Whether an employee gets paid or unpaid leave depends on their employment type, because the Fair Work Ombudsman's fact sheet confirms the thresholds are set by category:

• Full-time employees: 10 days of paid personal/carer's leave for each year of service, under s 96 of the Fair Work Act 2009 (Cth).
• Part-time employees: the same entitlement calculated pro rata, so a part-timer working half the ordinary hours accrues 5 days a year.
• Casual employees: no paid personal/carer's leave under the NES, but a right to unpaid carer's leave (2 days per occasion) and unpaid compassionate leave.

Paid personal/carer's leave accrues progressively during the year at a rate of one-26th of the employee's ordinary hours, and unused leave carries over into the next year. It does not expire, and it continues to accrue while the employee is on paid leave such as annual leave.

When an employee does take paid personal/carer's leave, s 99 requires you to pay the employee at their base rate of pay for the ordinary hours they would have worked in the period. The base rate excludes incentive-based bonuses, loadings, allowances, overtime and penalty rates, so a day of sick leave is not a day at penalty rates.

What counts as a good reason for sick leave

The legal test is set out in s 97 of the Fair Work Act 2009 (Cth). An employee may take paid personal/carer's leave if either of two things is true:

• the employee is not fit for work because of a personal illness or personal injury affecting them; or
• the employee needs to provide care or support to a member of their immediate family or household who requires it because of a personal illness, personal injury, or an unexpected emergency.

The same two limbs drive every absence you will see. Legitimate reasons include short-term illness such as colds, flu and gastrointestinal infections, injuries and recovery from surgery, flare-ups of chronic conditions such as migraine or asthma, mental health episodes, and pregnancy-related illness. The Ombudsman's guidance makes clear that stress and pregnancy-related illnesses are covered by the personal illness limb, so a mental health day is as legitimate as a physical one and should be treated consistently.

For the caring limb, immediate family is defined broadly. It includes a spouse or former spouse, a de facto partner or former de facto partner, a child, parent, grandparent, grandchild or sibling, plus the child, parent, grandparent, grandchild or sibling of the employee's spouse or de facto partner. A member of the employee's household is also covered, even if not a relative.

What is not covered matters just as much. The NES test is fitness for work or a qualifying caring obligation, not convenience. Personal errands, leisure, and routine non-urgent appointments are not personal/carer's leave. The Ombudsman's guidance on notice and medical certificates states that pre-arranged medical appointments and elective surgery can only be covered by sick leave if the employee is not able to work because of a personal illness or injury, and that it depends on the individual circumstance. A planned dentist visit or check-up is therefore not automatically sick leave, though you can agree to annual leave, unpaid leave, or a flexible arrangement instead.

You do not need a diagnosis, and you should not seek one. The question is always whether the employee was unfit for work, or had a qualifying caring obligation, not the medical label attached to it.

Your notice and evidence duties

The NES notice rule is in s 107 of the Fair Work Act 2009 (Cth). An employee taking leave under the personal/carer's leave provisions must give you notice as soon as practicable, which the Act expressly allows to be a time after the leave has started, and must advise the period or expected period of the leave. There is no prescribed number of hours in the Act, so you can set a practical expectation in your policy, such as notice before the start of a shift, provided the policy allows for genuine emergencies and after-the-fact notice.

On evidence, s 107(3) lets you require evidence that would satisfy a reasonable person that the leave is taken for a reason in s 97. The Ombudsman's guidance is that there are no strict rules about the type of evidence, but it must be enough to convince a reasonable person that the employee was genuinely entitled to the leave. A medical certificate or a statutory declaration are the standard examples of acceptable evidence. Critically, the Ombudsman confirms employers can ask for evidence for a single-day absence, so there is no rule that certificates only become reasonable from the second day. An award or enterprise agreement may specify when evidence must be given and what type is required, but the type requested must always be reasonable in the circumstances.

If the employee does not give notice or, when asked, evidence that would satisfy a reasonable person, they may not be entitled to be paid for the leave. That is the statutory lever, and it works only when applied consistently.

There are also firm boundaries on what you may not demand. The Ombudsman does not consider it reasonable to contact the employee's doctor for further information, and you should never request a diagnosis or private medical detail. Health information is sensitive. Collect only what is needed to assess the leave, limit access to people who genuinely need to know, and store records securely, remembering that personal information given to an employer may be regulated under the Privacy Act 1988 (Cth).

Paying leave and what happens when the balance runs out

When an employee still has accrued paid personal/carer's leave, s 99 governs payment: base rate for ordinary hours. Two situations cause the most confusion:

• Paid balance exhausted and still unfit for work: The NES does not provide unpaid leave for an employee's own illness, so there is no entitlement to draw on. The practical options are unpaid leave by agreement, annual leave if the employee requests it, or a flexible working arrangement where the role allows.
• Caring responsibilities after the paid balance is gone: Here the NES does step in. Under s 102, every employee including casuals is entitled to 2 days of unpaid carer's leave for each occasion on which an immediate family or household member needs care or support because of illness, injury or an unexpected emergency. Section 103 allows the leave as a single continuous period of up to 2 days, or separate periods to which you and the employee agree. An employee cannot take unpaid carer's leave for a period when they could instead take paid personal/carer's leave, though this limitation does not affect casuals, who have no paid balance.

A related rule on cashing out is worth knowing because employers occasionally offer it as a solution. Paid personal/carer's leave can only be cashed out where an award or enterprise agreement allows it, and then only with a separate written agreement each time, a remaining balance of at least 15 days, and payment of the full amount that would have been paid for the leave. Only two modern awards currently permit cashing out. Employees not covered by such an instrument cannot cash out sick leave at all.

Managing repeated absences, longer leave and return to work

For absences of two days or more, requiring a medical certificate is common and reasonable, but as noted you can request evidence from the first day when the circumstances justify it. The key is to state in your policy when evidence is required, what forms you accept, and how it should be submitted.

Frequent short absences, particularly clustered around weekends or public holidays, deserve a careful response rather than a blunt one. Have a private conversation, explain the pattern you have observed, and ask how you can support reliable attendance. Where appropriate you can tell the employee you will require evidence for future single-day absences for a period, provided the requirement is applied consistently across the workforce. Remember that repeated absences can signal workplace stress, workload problems or an underlying health condition, and support often achieves more than a warning.

For an extended absence, plan the return rather than assuming it. Where you reasonably need assurance that it is safe for the employee to perform the inherent requirements of the role, a fitness-for-work confirmation is appropriate, but keep the request proportionate and consistent with your policy. Consider temporary adjustments, graduated hours or different duties where medical advice supports them.

Nothing in the NES prevents an employee from taking personal/carer's leave during a notice period after resignation if they are genuinely unfit for work, and the same notice and evidence rules apply. A resignation does not convert a genuine illness into an unpayable absence.

Consequences of getting it wrong

The consequences of mishandling sick leave are real and specific.

Contravening an NES provision is itself a civil remedy provision under s 44 of the Fair Work Act 2009 (Cth). The Fair Work Ombudsman can investigate and take court action, and a court can order penalties calculated under the table in s 539 plus compensation for affected employees.

The general protections provisions create a second exposure. Section 340 prohibits adverse action against an employee because they have exercised a workplace right, and taking personal/carer's leave is a workplace right. Adverse action includes dismissal, injuring the employee in their employment, altering their position to their prejudice, and discriminating between employees. A warning issued, a roster changed, or a dismissal made because an employee took sick leave can all become an adverse action claim.

A third exposure sits in the unfair dismissal jurisdiction. Under s 385, a dismissal is unfair if it is harsh, unjust or unreasonable, and the Fair Work Commission can order reinstatement or compensation. A dismissal that follows a sick leave dispute without a fair process is exactly the kind of case that succeeds.

What reduces all three risks is the same thing: consistency. Evidence rules applied to everyone, mental health treated like physical health, and processes documented.

Compliance checklist for sick leave

Work through this checklist to keep your sick leave practices compliant:

• Confirm entitlements by employment type: 10 days for full-time, pro rata for part-time, and unpaid carer's leave for casuals.
• Set notice expectations in your policy, using the statutory baseline of as soon as practicable plus a practical deadline that allows for emergencies.
• State when evidence is required, including whether single-day absences need it, and what forms you will accept.
• Apply evidence and attendance rules uniformly across the workforce, and record that you have done so.
• Pay the base rate for ordinary hours and keep accurate records of accrual, rollover and days taken.
• Handle health information sensitively: collect only what is necessary, restrict access, and store securely.
• Use a respectful, documented process for absence patterns, longer absences and return to work.
• Train managers on the fitness-for-work test and on what they may not ask for.

When to get legal help

A lawyer is worth involving before you take disciplinary or dismissal steps over attendance, not after. That is when the cost of getting it wrong is highest and the factual record is still in your control. Legal help is also useful when you are drafting or updating a sick leave policy, when an adverse action or unfair dismissal claim is threatened, and in long-term illness or injury cases where other entitlements and schemes may interact.

A practitioner will review your policy against the NES and any applicable award or enterprise agreement, advise on a specific absence or pattern, draft return-to-work arrangements, and respond to claims if they are made.

Consistency is the duty employers miss most

Across sick leave disputes, the same misstep keeps appearing: selective enforcement. Requiring a certificate from a casual but not a full-timer, demanding evidence only for Monday absences, or treating a mental health day differently from a physical one. No single provision bans that behaviour in so many words, but it converts an ordinary absence into an adverse action or discrimination question, and it destroys the credibility of your process when an employee challenges it.

The first action to take this week is to pull out your leave policy and check whether the evidence rule it states is one you would apply to every employee, every time. If it is not, fix the policy before the next Monday morning call, because the employee who notices the difference is the one who will test it.