Thanks for reaching out in the community. If you would like to change the page size, please follow these steps:

1. Open Document Settings within the File menu.

2. Hit the "Size" drop down and select "Custom"

3. Enter the page size that you desire and these edits will be made on your document.

I hope this helps!

Doesn't help me. Nor the Author I suspect as the issue wasn't how to change the page settings every time but how to set them as a default.

I'm on the Trial Version and if it doesn't allow the Default page size default units etc... to be set permanently then i'm wasting my time.

Hi Thomas

If you would like to change the default page size for all documents you can do this within your Lucid Account Settings under the Lucidchart tab. Simply choose the default units, size, and format you’d like every document to start with!