The basic mechanism
The Ministry of Finance confirms that VAT was introduced across the UAE on 1 January 2018 at a standard rate of 5%. VAT is charged at each stage of the supply chain, but registered businesses recover the VAT they pay on costs used for taxable supplies. In the end, the tax is borne by the final consumer.
Two terms matter. Output tax is the VAT you charge on your sales. Input tax is the VAT you pay on purchases and expenses. Each tax period you report both on your VAT return and pay the difference, or claim it back if input tax is higher.