If you are a non-resident, you will be unable to register for online filing in the normal way as HMRC require you to have a National Insurance number (NINO) or a Unique Tax Reference (UTR) already. If you do not have either of these, you will need to contact HRMC. Our customers previously have been advised that they must paper file in the first year. Therefore you will be unable to use a third party software for the first year but will be able to the following years. 

Once you have a UTR (this is usually issued on a HMRC letter after your first submission), this means that you will be registered for Self Assessment and will be able to request your government gateway credentials which allow you to view your tax details online and file returns for subsequent years via their online portal.

Please note, once you have complete the registration for your government gateway account, you will need to use a third party software as the HMRC website does not contain the ability to complete and file the SA109 Residence and remittance supplementary pages through their online portal.