Stamp duty and SDRT (Stamp Duty Reserve Tax) definition
When investors trade in electronic share transactions (paperless) they must pay Stamp Duty Reserve Tax (SDRT). This applies to those types of transactions dealing in: shares in a UK company, shares in a foreign company that has a UK share register, options to buy shares, rights arising from shares you already own, and any interest in shares (such as an interest in the money made from selling them).
Most paperless share transactions that you pay SDRT on are carried out electronically through CREST, the electronic settlement and registration system administered by Euroclear. CREST automatically collects SDRT on the investor's behalf.
SDRT is still applicable to 'off-market' transactions, including if shares are transferred outside of CREST or held by a nominee. Brokers usually handles the SDRT, but investors can settle the SDRT themselves if they wish.
SDRT must be paid by the 'due date', which is the seventh day of the month following the month after you made the purchase. If shares were purchased on 15 January, then any outstanding SDRT is due to be paid by 7 February.
SDRT is a flat rate of 0.5% of the purchase price of the shares. If the value of the shares change, the amount of SDRT due remains the same.