The Unique Taxpayer Reference Number is the Number that every company gets while company formation. This Unique Taxpayer Reference Number is issued by the HM Revenue & Customs (Her Majesty’s Revenue and Customs ).If you set up a limited company in UK, it will be sent automatically to your registered address.
You can find here a sample bout how looks like the UTR Unique Taxpayer Reference Number.
Why do I need the Unique Taxpayer Reference ( UTR )?
The Unique Taxpayer Reference ( UTR ) is needed in order to identify the companies ba German authorities, when you need to take German VAT registration, so its a kind of tax ID that they take in consideration, in case youre not VAT registered in UK.
If you want to know what other documents are needed for get German VAT registration in Germany for online selling, you can read this article.
Hopefully this information provided is helpful for your. If you have any question, just let me know.