By DoctorCert Clinical Team
Private Medical Certificate vs NHS Fit Note: What's the Difference?
Not all medical documents are the same. Discover the key differences between a private medical certificate and a standard NHS fit note.
When you need medical evidence for time off work or study, you will encounter two main document types: the NHS fit note and the private medical certificate. While both confirm illness, they differ in how they are obtained, what they cost, and when each one is appropriate. This guide explains everything you need to know to choose the right option.
What Is an NHS Fit Note?
The NHS fit note - officially called a Statement of Fitness for Work - is a document issued by an NHS healthcare professional (usually your GP) stating that you are either unfit for work or may be fit for work with adjustments. It replaced the old-style "sick note" in April 2010.
NHS fit notes are free of charge and are the standard document used for Statutory Sick Pay (SSP) claims. However, getting one typically requires booking a GP appointment, which can involve waits of several days to weeks depending on your area.
Key features of an NHS fit note:
- Free to obtain
- Issued by GPs, hospital doctors, and some other healthcare professionals
- Required by law for SSP claims after 7 days of illness
- Can include return-to-work recommendations
- Typically requires an in-person or telephone appointment
What Is a Private Medical Certificate?
A private medical certificate is a document issued by a GMC-registered doctor outside the NHS that confirms you have been, or are currently, unfit for work. These are offered by private clinics, occupational health services, and online platforms like DoctorCert.
Private certificates are not free - they typically cost between £20 and £50 depending on the provider. However, they offer significant advantages in speed and convenience, especially when GP appointments are hard to come by.
Key features of a private medical certificate:
- Paid service (DoctorCert charges a flat £29)
- Issued by GMC-registered doctors
- Available same-day via online consultation
- Widely accepted by UK employers for short-term absences
- Delivered digitally - no need to visit a surgery
Side-by-Side Comparison
Here is how the two options compare across the factors that matter most:
Cost: NHS fit notes are free. Private certificates typically cost £20-£50.
Speed: NHS appointments can take days or weeks. Private certificates are often issued the same day.
Convenience: NHS usually requires a phone or in-person appointment. Private services work entirely online.
Employer acceptance: Both are widely accepted. For SSP, any registered medical practitioner qualifies.
Verification: NHS fit notes have a standard format. Private certificates from reputable providers include unique verification codes.
When Should You Use Each Option?
Choose an NHS fit note when:
- You need a note for a long-term illness (weeks or months)
- You have an existing relationship with your GP who understands your condition
- Your employer specifically requires an NHS fit note
- You cannot afford a private certificate
Choose a private medical certificate when:
- You need medical evidence urgently (same day)
- GP appointments are unavailable in your area
- You are too unwell to attend a surgery
- You need a certificate for a university or insurance claim rather than SSP
- You are away from your registered GP area
If you are trying to evidence an illness period after a delay, read our guide to whether a sick note can be backdated in the UK before deciding which route is most suitable.
Do Employers Accept Private Medical Certificates?
The short answer is: yes, in the vast majority of cases. UK employment law requires a "statement of fitness for work" from a registered medical practitioner for SSP purposes. A GMC-registered doctor - whether NHS or private - satisfies this requirement.
That said, a small number of employers have specific policies requiring an NHS fit note. If you are unsure, check your employee handbook or ask your HR department before ordering a private certificate.
Frequently Asked Questions
Is a private medical certificate legally valid?
Yes. A certificate issued by a GMC-registered doctor is a legitimate medical document. DoctorCert certificates include a unique verification code that employers can check.
Can I use a private certificate for Statutory Sick Pay?
The legislation requires a statement from a "registered medical practitioner." A GMC-registered private doctor qualifies. However, some employers may have their own policies. If in doubt, confirm with your HR team.
How quickly can I get a private certificate?
With DoctorCert, most certificates are issued within a few hours during business hours. You complete an online form, a doctor reviews your case, and the certificate is emailed to you.
Can I get a fit note for mental health?
Yes. Both NHS and private doctors can issue certificates for mental health conditions including stress, anxiety, depression, and burnout. These are among the most common reasons for workplace absence in the UK.
Get Your Certificate Today
If you need medical evidence quickly and cannot wait for a GP appointment, DoctorCert offers a fast, affordable alternative. Every certificate is reviewed and signed by a GMC-registered doctor.
Need a medical certificate?
If you need signed medical evidence for work, study, or administrative purposes, you can request a private medical certificate online from a GMC-registered doctor, usually issued within 2 hours during business hours. See the one-off pricing and how private medical certificates work before you start.
