Is there a grace period for online 90-day reports in Thailand?

There is no grace period for submitting the 90-day report online or via the app. It must be completed between 15 days before the due date and the due date itself. However, if submitted by traditional mail, it can be done 15 days before the due date. In-person submissions can be made between 15 days before and 7 days after the due date.