The most important tax for employees in Romania is the income tax. You pay income tax in monthly installments on all income in a calendar year – for salary income. If you work for a company as an employee, you don’t have to worry about income tax. Because your employer will automatically deduct income tax in the form of payroll tax from gross wages each month and transfer it to the tax administration. The employer also retains and transfers social security contributions.
Self-employed persons must declare income at the end of the fiscal year and pay income tax. Also, these persons have the legal obligation to conclude a health and pension insurance contract.
The EU and EEA citizens who are on the Romanian territory for a period of more than 183 days within a period of 12 consecutive months have the obligation to register their fiscal residence with the fiscal administration. They owe the payment of taxes and duties on all types of income as established by the Fiscal Code for Romanian citizens.
Documents to be provided:
Certificate for the recognition of the fiscal residence.
For more info:
https://www.mfinante.gov.ro/static/10/Mfp/legislatie/cod/law571_fiscal_code.pdf
http://www.oecd.org/tax/treaties/model-tax-convention-on-income-and-on-capital-2015-full-version-9789264239081-en.htm