This feature remains accessible in both the QuickBooks Essential and Plus editions. Allow me to assist you with the process, Mark.
All you need to do is to switch off the button on the QuickBooks Themes page.
- Click the Gear icon.
- Under Your Company, select Themes.
- Turn off the Dark Mode switch button.
You can check out the screenshot below for a visual guide.

If it doesn't return to the default theme, your browser may have accumulated too much historical data. Issues like this are usually the result of corrupt cache files in your web browser. Not to worry, you can clear them in a few easy steps.
First, try accessing your account in an incognito window. This helps eliminate potential webpage issues. Here are the shortcut keys to open an incognito window in different browsers:
- Chrome: Ctrl+Shift+N
- Firefox: Ctrl+Shift+P
- Safari: Command+Shift+N
If it's responsive, I recommend that you clear its cache. By clearing them, you can access QuickBooks with a clean slate. You can also switch to a different supported browser to see if it has something to do with your browser.
After successfully turning off dark mode, we can check QuickBooks again and review the financials if needed. If you need help with this in the future, I'll add this article: Run reports in QuickBooks Online.
I'm open to discussing any concerns you have about other settings in QuickBooks. I can also assist with topics related to reports, entries, and lists.