DT5452 - Double Taxation Relief Manual: Guidance by country: Czech Republic: Treaty summary
You should check the other guidance available on GOV.UK from HMRC as Brexit updates to those pages are being prioritised before manuals.
The table summarises the provisions of the treaty in force. Where a percentage rate is shown, this rate is the ‘treaty rate’ and does not reflect taxes chargeable under the domestic law of either state before relief is given under the provisions of the treaty. The ‘treaty rate’ is the maximum rate at which the UK and the Czech Republic are permitted to tax income in the relevant categories under the treaty. Rates chargeable under the domestic law of either state may be higher or lower.