Hi there, @memtecuk.
Thanks for bringing your concern to the Community. I'll be sharing steps to help you add payment terms in QuickBooks Online (QBO).
The option to add payment terms on an invoice template is still available in QBO. If it seems to have disappeared, it's possible that the browser cache has been stored for a long period of time, causing the browser to behave strangely.
To troubleshoot, I recommend trying to sign in to your QBO account using a private or "incognito" browser. This can help your computer or device run more efficiently by preventing interference from extensions, plugins, or cookies. Here are the shortcut keys for these browsers:
Also, clear your cache and refresh website preferences, which may cause issues with QBO.
Moreover, I'll be sharing these articles to help you learn how to receive and record invoice payments also, personalise your invoice, sales receipt, or estimate template to match your prefer style in QuickBooks Online:
We appreciate you visiting the Community space today. If you need help with any QuickBooks-related tasks, feel free to ask. Stay safe!
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