Day 16/30: Corporation Tax. What it is, what you pay and when. This is one of the topics that trips up first-time founders the most, especially international founders who are used to completely different tax systems. Here is the single most important thing to know: HMRC will not send you a bill. You are responsible for working out what you owe, paying it on time and filing your Company Tax Return yourself. Miss the deadline and the penalties stack up fast. The rates are straightforward. Up to £50,000 profit - 19%. Over £250,000 - 25%. Most early stage startups pay 19% or nothing at all if not yet profitable. What matters is that you understand the system, keep clean records from day one, and get the right support early. I am teaching you everything from my own experience of building in the UK. The tax side of running a company here is not as complicated as it sounds, but only if you know what you are dealing with before it catches you out. Save this post. Share it with a founder wh...