Must You Tell Your Employer About a Chronic Illness?
When you must disclose a chronic illness to your employer in the UK and US, when you can stay silent, and how medical information is protected.
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Whether you must tell your employer about a chronic illness depends on where you live. In the UK and the US there is generally no duty to tell, and a hidden disability is yours to share or to keep private. You can note each symptom and sick day with a date on paper or in the symptom diary in Sam. At the conversation you then say "six days last quarter" instead of "often".
This text is general information, not legal advice. Only a lawyer or adviser who knows your case can say what applies to you. In the UK that means ACAS, Citizens Advice, the Equality Advisory Support Service or an employment lawyer. In the US it means the Job Accommodation Network (JAN), the EEOC or an employment lawyer. What you say, and to whom, stays your decision.
Are you legally required to tell your employer?
In the UK and the US, there is no general legal duty to tell your employer that you have a chronic illness. The Equality Act 2010 in Great Britain (Northern Ireland has separate law) and the Americans with Disabilities Act (ADA) in the US protect many people with hidden conditions, even when nothing is said. The ADA covers employers with 15 or more employees, and some state laws reach smaller ones.
The main practical point is simple. Your employer can only act on what it knows. That is what makes disclosure matter.
Does a chronic illness count as a disability?
Under the UK Equality Act, you are disabled if you have a physical or mental impairment with a substantial and long-term adverse effect on your day-to-day life. "Long-term" usually means 12 months or more. The effect does not have to be constant, and fluctuating conditions can count.
Under the US ADA, a disability is a physical or mental impairment that substantially limits a major life activity. The ADA also protects people with a record of such an impairment, and people regarded as having one.
A chronic illness is not automatically a disability, but many are. Whether your own condition meets the test is a question for advice.
When does the duty to adjust start?
In the UK, the duty to make reasonable adjustments starts when your employer knows, or could reasonably be expected to know, that you are disabled and that you are disadvantaged because of it. ACAS says employers must act when they know, or should know, and when a disabled worker asks for changes.
In the US, the duty to provide a reasonable accommodation generally starts when you ask. The EEOC notes that employers act on limitations they know about, and it is usually the employee who makes them known. You can request accommodation at any time, even if you said nothing when you were hired.
Disclosure is often the price of protection. If you never tell your employer, it cannot adjust a workstation, a shift or a policy for you.
What about health and safety at work?
Employers have a duty of care and health and safety duties in both countries. If your condition could create a risk in your job, the picture can change.
In safety-critical roles, such as driving, heavy machinery or healthcare, you may need to talk to your employer and your doctor about what is safe. The right answer depends on the role and the condition. This text cannot settle it. When time off is part of the picture, the explainer on FMLA intermittent leave covers the US side.
How is your medical information protected?
In the US, the ADA requires employers to keep disability-related information confidential and in separate medical files. In the UK, health information is a special category of personal data under data protection law, so your employer should keep it confidential and use it only where it is needed.
Coworkers have no right to your diagnosis. You are not required to tell them.
What can you share, and with whom?
When you decide to speak, there are levels of detail. You do not have to start with the name of your condition.
- The name of your illness, if you choose.
- How it affects your work, for example which tasks are hard on some days.
- A document, such as a note from your doctor or a summary of your record.
Match the level to the person and the reason. For an adjustment, you usually need to say enough for your employer to grasp the disadvantage. How to ask for reasonable adjustments walks through that.
How do you prepare the conversation?
Decide what you want first: an adjustment, understanding or simply rest. Then choose the level of detail and get advice in advance.
A dated record helps you speak in numbers. The doctor visit checklist for a chronic condition shows what is worth gathering. You can keep sick days and everyday symptoms in the symptom diary. For a diagnosed condition, the doctor report inside its diary sums up a period as a PDF.
Keep your dated record in Sam and take it to the conversation
A dated record lets you name real numbers instead of estimates, and none of it has to name your illness. You keep it in the symptom diary.
- Instead of memory: every symptom day and sick day sits with a date, so "six days last quarter" replaces "often".
- Instead of loose notes: if a diary program for your condition runs in Sam, the doctor report as a PDF sums up the period you choose for your GP or your own files.
- Instead of screenshots: for migraine and epilepsy, new entries made today bring in last night's sleep and heart rate variability from Apple Health when a value exists.
Sam sends nothing to your employer on its own. What you show, and to whom, is yours to choose.
Try Sam HealthSam is a wellness companion, not a medical device. The app does not diagnose, treat, cure or prevent any condition or health state. Always consult qualified professionals for medical decisions.
General information, not legal advice. Laws, deadlines and agency practice change, and your case may differ. Before applications, deadlines and conversations with employers, insurers or agencies, get advice from an adviser or lawyer.
Related reading
- How to ask for reasonable adjustments at work
- Doctor visit checklist for a chronic condition
- FMLA intermittent leave and documentation for migraine and epilepsy
- Exam Accommodations for a Chronic Illness: UK and US
Sources
Updated: October 2026
- ACAS: Reasonable adjustments at work (last updated 30 January 2025)
- ACAS: What disability means by law (last updated 8 January 2025)
- GOV.UK: Definition of disability under the Equality Act 2010
- Citizens Advice: Asking your employer for changes to help you if you're disabled
- EEOC: Your employment rights as an individual with a disability
- JAN: Disability disclosure and the ADA
- ACAS: Asking for reasonable adjustments (last updated 30 January 2025)
- legislation.gov.uk: Equality Act 2010, section 60
- ICO: What is special category data?
- EEOC: Disability discrimination and employment decisions
More on recording and taking it along
Frequently Asked Questions
Must I tell my employer about my chronic illness?+
As a general rule, no. In the UK, nobody has to tell their employer they are disabled, and in the US the ADA does not force you to share one either. The practical exception is that your employer has to know about a disability before the duty to make reasonable adjustments or provide reasonable accommodation can apply to you.
Can my employer ask about my health?+
In the US, an employer generally cannot ask disability-related questions before a job offer, and after you start only if the question is job-related and a business necessity. In Great Britain, section 60 of the Equality Act 2010 stops an employer asking about your health before a job offer, with narrow exceptions, and health data is special category data under UK GDPR. On a lawful question you should answer truthfully.
What happens if I never tell my employer?+
Your employer can only act on what it knows, so it cannot adjust a workstation, a shift or a policy for you. In the UK the duty to make reasonable adjustments starts when your employer knows, or could reasonably be expected to know, that you are disabled. In the US it generally starts when you ask.
Is my medical information kept confidential?+
Yes. Under the US ADA, disability-related information must be kept confidential and held in separate medical files. In the UK, health data is a special category of personal data under data protection law, so your employer should keep it confidential and use it only where needed. Coworkers do not have to know your diagnosis.
What should I do if my condition affects safety at work?+
Employers have a duty of care and health and safety duties in both countries. If your condition could create a risk in a safety-critical role such as driving or operating machinery, you may need to discuss it with your employer and your doctor. What applies to your job is for an adviser or lawyer to say.
Who can advise me before I say anything?+
In the UK, ACAS, Citizens Advice, the Equality Advisory Support Service or an employment lawyer. In the US, the Job Accommodation Network (JAN), the EEOC or an employment lawyer. Advice before a conversation is nearly always worth it, because your case is individual.