A fit note — formally a Statement of Fitness for Work — is the UK’s medical evidence for sickness absence, issued by a registered healthcare professional. It replaced the “sick note” in 2010, redesigned to say what someone can do rather than only what they can’t. That redesign is the most misunderstood thing about it.

What’s actually on it

The issuer ticks one of two options. There is no third.

• Not fit for work
• May be fit for work taking account of the following advice

Choose the second and four suggestions become available: a phased return to work, altered hours, amended duties, workplace adaptations. There’s space to explain the condition’s effect on work, and the issuer can set a review date.

Note what’s missing. There is no “fit for work” box. An employee returning early doesn’t need a note clearing them — asking for one is asking for a document that doesn’t exist.

The part employers get wrong

The fit note is advice, not instruction. If you can’t accommodate the suggested adjustments, you aren’t obliged to — and you don’t need a revised note. The existing one becomes evidence the employee is not fit for work, and your sick pay process runs as normal.

One warning: where a fit note raises a possible disability, the reasonable adjustments duty under the Equality Act applies regardless. That obligation doesn’t wait for a tick box.

Notes can be issued after a face-to-face, video or telephone consultation, or on another clinician’s written report, and since 2022 they carry the issuer’s name and profession rather than an ink signature. Doctors, nurses, occupational therapists, pharmacists and physiotherapists can all issue them. In the first six months of a condition, one can cover a maximum of three months at a time.

When you can ask for one

Not before day eight. For seven calendar days or less, including weekends, employees self-certify, and a clinician may decline to issue a note inside that window anyway. You can require written self-certification; you can’t require medical evidence, or insist someone buy a private certificate — though you can accept one by agreement.

This matters more than it used to. Since 6 April 2026, Statutory Sick Pay starts on the first day of absence rather than the fourth, and the lower earnings limit has gone. Short absences now cost money from day one, which makes an accurate self-certification process worth having.

What’s changing

In May 2026 the government called the system “broken” and launched four pilots in England. The figure behind it: around 11 million fit notes a year, more than nine in ten saying “not fit for work.” A form built to start a conversation is being used as a binary permission slip.

The pilots run at NHS WorkWell sites in Birmingham and Solihull, Coventry and Warwickshire, Cornwall and the Isles of Scilly, and Lancashire and South Cumbria, testing personalised “stay in work” and “return to work” plans in place of the note — in Cornwall, with no note issued at all. Nothing has changed in law yet.

Frequently asked questions

How long can you be off sick without a fit note? Seven calendar days, weekends and bank holidays included. From the eighth day, an employer can require one.

Does an employer have to follow fit note advice? No, it’s advisory. If you can’t accommodate it, the employee is treated as not fit for work and no new note is needed.

Do you need a fit note to return to work? No. There’s no “fit for work” option on the form, and none is required to come back.