Sick Note vs Fit Note: Is There a Difference?
A sick note and a fit note are the same document. "Fit note" is the official UK name, introduced in April 2010 to replace the older "sick note" system. The formal title is the Statement of Fitness for Work (Med3 form). Most people still say "sick note" in everyday conversation, but the legal document your doctor issues is always a fit note.
The name change was not cosmetic. It reflected a shift in how UK medical evidence works. Under the old sick note system, a doctor could only declare you unfit for work. The fit note added a second option: you may be fit for work if your employer makes certain adjustments, such as reduced hours, lighter duties, or a phased return. This means the document now actively supports recovery rather than simply recording absence.
Whether you search for "sick note" or "fit note," you will receive the same medical certificate from the same healthcare professionals, governed by the same employment law. The distinction matters only in understanding what the document can say about your ability to work.
Sick Note vs Fit Note: Side-by-Side Comparison
| Feature | Old Sick Note (pre-2010) | Modern Fit Note (2010 onwards) |
|---|---|---|
| Official name | Medical Statement (Med3) | Statement of Fitness for Work (Med3) |
| What it can say | Unfit for work only | "Not fit for work" or "May be fit for work" with adjustments |
| Workplace adjustments | Not included | Doctor can recommend phased return, amended duties, altered hours, or workplace adaptations |
| Who can issue it | GPs and hospital doctors | GPs, hospital doctors, registered nurses, occupational therapists, pharmacists, physiotherapists (expanded from July 2022) |
| Format | Paper only | Paper or digital (the requirement for a signature in ink was removed on 6 April 2022) |
| Used for SSP | Yes | Yes |
| Used for ESA/Universal Credit | Yes (historically) | Yes (NHS Med3 only, not private certificates) |
| Still in use | No, replaced in 2010 | Yes, current UK standard |
The table above summarises the practical differences. The core change is that the fit note gives doctors a way to support a managed return to work, rather than defaulting to complete absence. This benefits employees who could work with reasonable adjustments, and employers who want to retain staff through illness rather than lose them to prolonged absence.
The Two Outcomes on a Fit Note
Every fit note contains one of two assessments. Understanding which one applies to you affects how your employer should respond.
"Not Fit for Work"
The healthcare professional's clinical opinion is that you should not work at all during the period covered by the note, and the note is the medical evidence of that for your employer. You do not need a separate return to work certificate if you recover before it expires. GOV.UK is explicit that people do not need to be signed back to work and that there is no option on the fit note to do so, so you can simply go back when you feel ready.
"May Be Fit for Work"
The doctor believes you could return to work if your employer makes specific adjustments. These might include amended duties, altered hours, a phased return, or workplace adaptations. Your employer should discuss these with you. GOV.UK describes the fit note as advice to help you and your employer discuss support, and the suggested options are not binding on the employer. If no agreement on changes is reached, the employee must be treated as not fit for work for the period covered, and does not need a new or revised note.
This two-outcome structure is the defining feature that separates the modern fit note from the old sick note. It gives employees and employers a framework for having a constructive conversation about return-to-work options, guided by medical advice.
Who Can Issue a Fit Note in the UK?
The range of healthcare professionals authorised to issue fit notes expanded significantly in July 2022. Before that date, only doctors (GPs and hospital doctors) could sign fit notes. The change was introduced to reduce pressure on GP appointments and improve access for patients.
The instrument is the Social Security (Medical Evidence) and Statutory Sick Pay (Medical Evidence) (Amendment) (No. 2) Regulations 2022 (SI 2022/630), in force from 1 July 2022. It defines a healthcare professional as a registered medical practitioner, a registered nurse, a registered occupational therapist, a registered physiotherapist or a registered pharmacist. The following healthcare professionals can therefore issue a fit note:
💉 Doctors
GPs and hospital doctors. This includes both NHS and private GMC-registered doctors.
🩺 Nurses
Registered nurses, including practice nurses and specialist nurses.
🧹 Occupational Therapists
Particularly relevant for workplace-related conditions and return-to-work planning.
💊 Pharmacists & Physiotherapists
Added by SI 2022/630 to improve patient access. The pharmacist limb reads registered pharmacist within the meaning of the Pharmacy Order 2010, with no independent prescriber restriction attached to it.
A fit note from any of these professionals carries the same legal weight. Your employer cannot reject a fit note because it was issued by a nurse rather than a doctor.
When Do You Need a Fit Note?
The 7-Day Self-Certification Rule
For the first 7 calendar days of illness (including weekends and bank holidays), you do not need a fit note. You can self-certify your absence. Your employer may ask you to complete a self-certification form (SC2) when you return. A fit note applies only where the absence runs to more than 7 consecutive calendar days, that is, from the 8th day onwards. This rule is set out in GOV.UK guidance on taking sick leave.
| Absence Length | Documentation Required | Who Provides It |
|---|---|---|
| Days 1 to 7 | Self-certification (SC2 form or employer's own form) | The employee |
| Day 8 onwards | Fit note (Statement of Fitness for Work) | GP, hospital doctor, nurse, OT, pharmacist, or physiotherapist |
Some employers request a fit note before day 8 as a matter of company policy, but they cannot legally require one during the self-certification period for Statutory Sick Pay purposes.
Private Medical Certificate vs NHS Fit Note
A private medical certificate is not a fit note. Only the professions named in SI 2022/630 can certify a fit note, and a fit note is the prescribed form of evidence for social security and Statutory Sick Pay purposes. GOV.UK guidance for patients says that private medical certificates may be accepted by your employer as medical evidence in the same way as a fit note, but that this is subject to their agreement. The second difference is that a private certificate cannot support a government benefit claim.
| Feature | NHS Fit Note (Med3) | Private Medical Certificate |
|---|---|---|
| Issued by | NHS GP or hospital doctor | Private GMC-registered doctor (including online services) |
| Accepted by employers | Yes | Subject to the employer's agreement |
| Valid for SSP | Yes | Only where the employer agrees to accept it as evidence |
| Valid for ESA / Universal Credit | Yes | No |
| Cost | Free via NHS | Paid (typically issued same day) |
| Waiting time | Depends on GP availability (often 1 to 3 weeks) | Usually same day or next morning |
⚠️ Important: Med3 Limitation
A private medical certificate is not a fit note. It cannot support a government benefit claim, including Employment and Support Allowance (ESA) or Universal Credit. If you need documentation for a benefit claim, you need a fit note from an NHS healthcare professional. A private certificate can be used for employer absence records, and as Statutory Sick Pay evidence where your employer agrees to accept it.
For many employees a private medical certificate answers the same practical need. It confirms your condition to your employer and supports your absence record, and where your employer agrees to accept it, it can serve as their evidence for Statutory Sick Pay. Acceptance is their decision, so it is worth checking your absence policy first. The private route is most useful when a GP appointment is not available within the timeframe your employer requires.
If a doctor cannot issue a certificate on clinical grounds, you receive a full refund.
Fit Notes and Statutory Sick Pay
A fit note is the primary piece of medical evidence used by employers to process Statutory Sick Pay (SSP). Under the current rules (updated April 2026), SSP is payable from day one of absence since 6 April 2026, when the three waiting days were abolished, and the lower earnings limit has been removed, meaning part-time workers and those on zero-hours contracts now qualify.
The current SSP rate is £123.25 per week, or 80% of average weekly earnings, whichever is lower. In practice, most employees receive the flat rate. The 80% formula only applies to lower earners whose 80% of average weekly earnings is less than the flat rate. Many employers offer contractual sick pay above this statutory minimum. A fit note provides the documentation your employer needs to process SSP. A private medical certificate can do the same for absences beyond 7 days, but only where your employer agrees to accept it in place of a fit note.
For a full explanation of SSP rules and employer obligations, see Sick Note for Work.
Common Questions About Sick Notes and Fit Notes
Is a sick note the same as a fit note?
Yes. "Sick note" and "fit note" refer to the same document. The UK government renamed the sick note to the "Statement of Fitness for Work" (fit note) in April 2010. The change reflected a shift from simply certifying absence to assessing whether an employee could return to work with adjustments. Both terms are widely understood by employers, HR departments, and payroll teams.
What replaced the old sick note?
The fit note replaced the old-style sick note in April 2010. The key change was adding a "may be fit for work" option alongside the existing "not fit for work" assessment. This allows doctors to recommend workplace adjustments such as amended duties, altered hours, or a phased return, rather than defaulting to complete absence.
Can I still ask my doctor for a sick note?
Yes. Your doctor will understand exactly what you mean. In practice, most people still say "sick note" and every GP, nurse, and pharmacist in the UK knows this refers to a fit note. The document you receive will be titled "Statement of Fitness for Work" regardless of what you call it when requesting it.
Who can issue a fit note in the UK?
GPs, hospital doctors, registered nurses, occupational therapists, pharmacists, and physiotherapists can all issue fit notes. This expanded list took effect on 1 July 2022 under SI 2022/630, which amended the Social Security (Medical Evidence) Regulations 1976 and the Statutory Sick Pay (Medical Evidence) Regulations 1985. Previously only doctors could sign fit notes. Private GMC-registered doctors issue private medical certificates rather than fit notes, and your employer accepts those at their discretion.
Do I need a fit note for 1 week off work?
No. For absences of 7 calendar days or fewer (including weekends and bank holidays), you can self-certify your illness. Your employer may ask you to complete a self-certification form when you return, but they cannot require a fit note during this period. A fit note is only legally required from the 8th calendar day of absence.
Can I get a fit note online?
A fit note itself comes from an NHS healthcare professional, and since 6 April 2022 it no longer has to be signed in ink, so it can be issued and sent digitally with the same legal weight as a paper one. A private online service is a different thing: it issues a private medical certificate, not a fit note. That certificate can be used for employer absence records and, subject to your employer agreeing, as their evidence for Statutory Sick Pay. It cannot support an ESA or Universal Credit claim.
Can my employer reject a fit note?
An employer cannot override the clinical opinion recorded on a fit note by substituting their own. A note saying not fit for work is the healthcare professional's clinical assessment of the period covered, and your employer should not require you to work against it. Where the note says may be fit for work with adjustments, GOV.UK is clear that the advice is not binding: the employer is not obliged to agree, but is encouraged to take it into account and discuss the options with you. If the adjustments cannot be accommodated, you must be treated as not fit for work for the period covered, and you do not need a new or revised note.
Can I go back to work before my fit note expires?
Yes. GOV.UK states that people do not need to be signed back to work and that there is no option on the fit note to do so. If you feel well enough to return before the end date, you can simply go back, and the patient guidance confirms you do not need to see your healthcare professional again first. Your employer may ask you to confirm in writing that you feel fit to return.
Is a private sick note valid for my employer?
Usually, but it is your employer's decision. GOV.UK guidance for patients says a private medical certificate may be accepted by your employer as medical evidence in the same way as a fit note, subject to their agreement, so check your absence policy. A private certificate is not a fit note, so it cannot support a government benefit claim such as Employment and Support Allowance or Universal Credit.
What does a fit note look like?
A fit note is a standardised form titled "Statement of Fitness for Work." It includes the date of assessment, the condition affecting your fitness for work, the doctor's assessment ("not fit for work" or "may be fit for work"), any recommended workplace adjustments, the period the note covers, and the issuing clinician's details. Digital fit notes are sent electronically and contain the same information as paper versions.
Sources and Further Reading
- GOV.UK: Taking Sick Leave
- GOV.UK: Fit Note Guide for Patients and Employees
- GOV.UK: Statutory Sick Pay
- ACAS: Absence from Work
- SI 2022/298: Social Security (Medical Evidence) and Statutory Sick Pay (Medical Evidence) (Amendment) Regulations 2022, in force 6 April 2022, which removed the ink signature requirement
- SI 2022/630: Social Security (Medical Evidence) and Statutory Sick Pay (Medical Evidence) (Amendment) (No. 2) Regulations 2022, in force 1 July 2022, which expanded the professions that can certify a fit note
