How to write a sick leave message to your boss, by text or email
Short, early and clear. You don't owe anyone a medical report, just the facts they need to plan the day.
A good sick leave message to your boss says four things: you're sick, you won't work today (or for how long), what happens to urgent work, and when they'll hear from you next. Send it as early as you can, before your shift starts. For example: “Hi Sarah, I'm sick today and won't be able to come in. I'll check messages at noon. Ali can cover the 10 am call.”
You don't need to describe your symptoms or apologise many times. Below are copyable versions for WhatsApp or text and for email, each in three tones. Pick the one that matches how you normally talk to your manager.
Which tone to pick
- Formal: a new job, a strict workplace, a manager you call Mr or Ms, or a company where leave goes through HR by email.
- Neutral: most offices. Polite and short. If you're not sure, use this one.
- Casual: a small team and a manager you chat with every day.
Check your company's policy too. Some workplaces want a phone call, a form, or a doctor's note after a certain number of days.
WhatsApp or text message
Keep it under 50 words. Your boss is reading it on a phone, maybe before breakfast. Copy a message, then replace the parts in [square brackets] with your own details.
Good morning Mr Patel. I'm unwell today and won't be able to come to work. I'll keep my phone on for anything urgent, and I'll update you tomorrow morning. Sorry for the short notice.
Hi Sarah, I'm sick today and won't be able to come in. I've moved my 2 pm meeting to Thursday. I'll check messages at lunchtime in case anything urgent comes up.
Hey Tom, I woke up with a bad fever, so I'm taking a sick day. Ali knows where the client files are. I'll let you know about tomorrow tonight.
Hi Sarah, the doctor has told me to rest until Wednesday, so I'll be off Monday and Tuesday. I've handed the report to Maria. I'll send you the doctor's note when I'm back.
Just need a text to paste? The sick leave text templates page has copy-ready WhatsApp versions, plus a day-two update.
Use email when your company expects a written record, when you need to copy HR, or when you'll be off for several days.
Subject: Sick leave: [date]
Dear Ms Rossi,
I'm writing to let you know that I'm unwell and won't be able to work today, [date]. I expect to be back on [date], and I'll confirm by [time] tomorrow.
[Colleague] has agreed to handle [urgent task] while I'm away. For anything else, I'll reply as soon as I can.
I'll send a doctor's note if it's needed.
Kind regards,
[Full name]
Subject: Off sick today
Hi David,
I'm not feeling well and won't be working today. I've moved my calls to Thursday and let the client know. I'll check email around noon in case something urgent comes up.
I'll update you tomorrow morning.
Thanks,
[Name]
Subject: Sick day
Hi Jen,
Bad cold, so I'm taking today off. Nothing urgent is due. The draft is in the shared folder if anyone needs it.
Back tomorrow, I hope!
[Name]
Phrases that help, and phrases to avoid
| Instead of | Why | Try |
|---|---|---|
| I am not feeling good since yesterday. | Wrong tense for something still going on. | I've been unwell since yesterday. |
| Kindly grant me leave for today. | Sounds like you're asking permission to be sick. | I won't be able to work today. |
| I will not come today. | Sounds blunt, like a choice. | I won't be able to come in today. |
| I have fever. | Missing a (but “I have flu” is fine in British English). | I have a fever. |
| I'm sick. Sorry. Sorry again. | One apology is enough. | Sorry for the short notice. |
| I'll be absent. | Fine, but sounds like school. | I'll be off today. |
A note on details: “I'm unwell” or “I'm sick” is enough. If you want to say more, keep it general: a fever, a migraine, a stomach bug, a bad cold. You never need to share private medical information with your manager.
What to do after you send it
- Turn on an out-of-office reply if you'll be off for more than a day: “I'm out sick today and will reply when I'm back on Wednesday. For urgent questions, please contact Ali at ali@company.com.”
- Update your boss at the time you promised, even if the answer is “still sick”.
- When you're back, a short “Thanks for covering, Ali” goes a long way.
If you're writing on WhatsApp, read what's OK and what sounds rude in WhatsApp messages to your boss. For a planned day off rather than a sick day, use the leave request in how to write a formal email. And if English isn't your first language, you can check the message in WhatsApp before you send it, so a grammar slip doesn't make a short message sound rude.
Questions
How do I tell my boss I'm sick by text?
Send a short message before your shift: say you're sick, that you won't work today, what happens to urgent work, and when you'll update them. For example: “Hi Sarah, I'm sick today and won't be able to come in. I'll check messages at noon.”
Is it OK to send a sick leave message on WhatsApp?
In many workplaces, yes, especially if your team already uses WhatsApp. Check your company's policy: some require a call, an email to HR or a form, even if you also send a WhatsApp message.
Do I have to say what illness I have?
No. “I'm sick” or “I'm unwell” is enough in most countries. Your workplace may ask for a doctor's note after a few days, but your manager doesn't need medical details in a message.
Should I apologise for being sick?
You don't need to. Getting sick isn't a mistake. “Sorry for the short notice” is a polite, optional line if you're messaging just before your shift.
What should I write if I'm sick for several days?
Give an expected return date, say who is covering urgent work, and promise an update: “The doctor has told me to rest until Wednesday. Maria has the report. I'll send you the doctor's note when I'm back.”
