When you need to call in sick in Sweden, inform your employer as soon as possible—preferably before the workday starts. You usually don’t need a doctor’s note for the first week of illness, but you won’t get paid for the first day off, known as the "karensdag".

If your illness extends beyond a week, you’ll need to see a doctor for a medical certificate. After 14 days, Försäkringskassan takes over the payment of your sick leave benefits. It's also best practise to check with your employer and/or manager about any company specific policies or guidelines regarding sick leave as well.