HMRC has revealed the most popular questions - and answers
Certain other people may need to send a return (for example ministers of religion or Lloyd’s underwriters) - you can check whether you need to. You usually won’t need to send a return if your only income is from your wages or pension.
When you fill in a tax return online, it automatically works out and displays how much tax and class 4 national insurance contributions you owe. It will also allow you to print your calculation.
You can register on GOV.UK. During registration, you’ll be given a User ID and will be asked to choose a password - naturally, you’ll need these when you login again.
We’ll then send you an activation code by text. Once you’ve activated the service, you can fill in your return.
It happens to the best of us! If you have problems signing in, there a number of ways to reset and gain access to your tax account. Watch HMRC's YouTube tutorial to find out more.
Your online self-assessment tax return needs to be in by 31 January 2018, otherwise you will receive a £100 fine.