There are 2 ways for getting VAT number in Estonia.   You can register the OU company and apply for the VAT number.   VAT Registration in Estonia is compulsory if you exceed VAT threshold – turnover > 40 000 EUR / on a yearly basis.   Naturally, you have the right to voluntary VAT registration.  After you are provided with VAT number- you can verify it on VIES website and remember – as VAT payer you are obliged to filling VAT returns – on the 20 days of next month for the previous month.