How do I file a UK Self Assessment Tax return Online
If you’re sending HM Revenue & Customs (HMRC) a Self Assessment tax return, you can do it online using the secure service HMRC provides.
If you’re newly self-employed, HMRC will set up your Self Assessment Online account automatically when you register for business taxes.
If you’re setting up a partnership, a Self Assessment Online account will automatically be set up for the Partnership.
In all other cases, you’ll need to sign up to use HMRC Online Services yourself.
Information you need before you start
You’ll need the following information:
your Unique Taxpayer Reference (UTR) number
either your postcode or National Insurance number (unless you live abroad)
You’ll find your UTR on correspondence from HMRC. If you can’t find it, you can contact the Self Assessment Helpline and ask for it to be sent to your home address. HMRC can’t tell you your UTR over the phone.
If you haven’t completed a tax return before (or it’s been a while since you did), you may not have a UTR. You’ll need to tell HMRC why you need a tax return, by registering for Self Assessment, so you can get a UTR
If you’ve already registered for HMRC Online Services and activated your Self Assessment Online account, use the link below to log in and use Self Assessment Online link on HMRC website and its easy to follow step by step process.