Why does QB not have a postcode lookup after people have been asking for it for years? sage here I come as it's been driving me mad for years. yours 25year QB user?

Hello there, @deshills. I'm here to share information about your postcode concern. 

Currently, the postcode lookup option is unavailable in QuickBooks Online (QBO). To request the addition of this feature, you can send feedback to our product developers. Here's how to do it:

1. Navigate to the Gear icon.
2. Then, select Feedback.
3. Enter your comments or product suggestions. Example: Have postcode lookup option in QuickBooks Online.
4. Then click Next to submit feedback.

Once done, feel free to visit our QuickBooks Online Feature Requests website to track the status of your submitted feedback. 

In the meantime, you can use the Map link located in the Address section of the Customer or Supplier Information, to search for an address using postcode. I've added a screenshot for your reference: 

You may also want to visit our Help page to check guides and articles that will help your QBO navigation. From here, you'll find a number of help articles and even video tutorials based on the QBO feature you've searched. You can also bookmark them in your browser for easy access and use them as your future reference.

I'm always around if you have any other QuickBooks concerns. Don't hesitate to post again here. Take care.