Let me share some information on how you can track your private pension contributions in QuickBooks.
The categories available in the system is aligned with the SA103F deduction categories you can claim as allowable expenses for self-employment. You'd want to tag these contributions as Other Business Expenses. Once you're ready to file your return, you'd have to manually enter or itemized these contributions. You can read through this article for more insights: About SA103F Categories.
Also, I'd recommend consulting with a Tax Professional or an accountant so you'd be guided in categorizing your pension contributions accurately. You can visit the Accountants Near Me | Chartered Accountants page to help find an expert.
Stay in touch if you have any other concerns or questions about tracking your self-employed related transactions. I’ll get back to answer them for you.