How long do I have to make a complaint? The NHS has a time limit for complaints. Normally, you must make your complaint within six months of: The event you want to complain about, or Finding out you have a reason to complain, but no longer than 12 months after the event itself. However, if you feel the time limit should not apply to your complaint, please speak to the person dealing with it. A complaint can sometimes be accepted after the time limit. You can complain to the Scottish Public Services Ombudsman about an NHS decision not to accept your complaint. What if I change my mind after I have complained? You can change your mind about making a complaint at any time. Please let the person handling your complaint know as soon as possible.