This paper aims to provide an up-to-date evidence base on the costs of administering a wealth tax based on the experience from taxes on wealth that currently exist in the UK and information from other countries that currently impose a wealth tax or have done so in the past. It should be emphasised that these costs crucially depend on design choices. Motivated by this observation, the paper throughout links the presented evidence to the corresponding policy features. Estimatated costs are provided for both taxpayers and the tax authority.