If you're new to Self-Assessment or uncertain about whether you should submit a return, this article provides guidance. Typical reasons involve being self-employed, earning over £100,000, or having income from sources not subject to taxation. Inform HMRC by the deadline of October 5, 2023, for the 2022/23 tax year. The article recommends using HMRC's online tool for clarification and outlines various scenarios that require filing. Seek assistance if in doubt.