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Let me guide you through the steps in removing the page numbers at the bottom of your estimates in QuickBooks Online (QBO).
QBO has various templates you can choose from. You can consider trying other templates except for the Airy new since it's the only template that has a page number. Here's how:
Go to the Gear icon, then select Custom form styles.
Click on the New style dropdown and choose Estimate.
Under the Design tab, enter your template name.
Hit Change up the template.
From there, you can choose whatever template except for the Airy new.
You can also customize your template if needed.
Once finished, click Done.
Moving forward, you can already create an estimate using the Custom form style you created. Here's how: