Certificate of Tax Residence

I would like to request a Certificate of Tax Residence from the UK to submit it in the tax authorities of my home country (Greece) to avoid double taxation. I work in the UK since 1 August 2022 under a Skilled Worker Visa. I have personal income only in the UK, and I receive interest from a savings bank account in Greece. I can't use the online service, because I do not have an NFC mobile phone to use the app and I do not have 2 of the requested documents to verify my identity (I have only one of them). For this reason, I used the email form and completed it with as much details as possible. However, I received the following email: "Unfortunately, i am unable to verify your residency status please send in evidence you were a UK resident for this period including UK address you have lived at. In addition please complete the residency test on the link below." I completed the residency test and I am a tax residence in the UK for the previous tax year (6 April 2022 to 5 April 2023), because I have been in the UK for 249 days. I have already submitted evidence for my UK address to the Home Office as part of my visa status, and I am also registered in the local electoral register. I thought that you have access to this information when I submitted my application. My question is where I should submit the evidence that I was living in the UK and what kind of evidence I should submit. I have UK Entry Clearance (including the stamp with the date I entered in the UK), rental contract, bank statement, and work contract. The email form does not have the option to upload documents and the email I received states "Please do not reply directly to this email."

Hi lb1991,
The guidance in Annex A details the type of documentary evidence you should provide  to HMRC to have your residence in the UK verified.
The HMRC address to which you should send the documentaion (with a covering letter) is also provided in the link below.                                                    
Annex A: documentary evidence of continuous residence in the UK                                                                  
Income Tax: general enquiries
Thank you. 

I submitted the documents to update my HMRC address by post office 3 months ago, but the address has not changed in my personal tax account yet. I managed to change my postal address online, but when I try to change my main address, I get the following error: "The date you entered is earlier than a date previously held on your address record." Thank you.

Hi

If you did not enter a start date when you updated it online, it will automatically default to the date you done the update.
You now cannot enter the date you moved as this will be earlier and will need to put in a date later that the original online update.

Thank you