Once you are on the company for the Director or PSC you wish to view the code for.

You can navigate to the Officers or PSC section and then click the button with an arrow next to the record you wish to view the code for. The personal code will then viewable in this section under "Companies House personal code"

Checking codes across all of your clients? If you want to check personal codes across your whole portfolio (i.e. all of your client companies) at once, rather than one record at a time, see How to generate a report of personal codes entered.