How Much Is A Private ADHD Assessment? If you'd like to be able to reduce the length of time you wait for an ADHD assessment, you can do so by paying privately. This is referred to as Your Right to Choose and is accessible to all registered GPs in England. https://telegra.ph/10-Tell-Tale-Signs-You-Need-To-Get-A-New-Private-ADHD-Testing-UK-03-07