Hi Remi123, 

It would be more helpful to get further details about converting your data to QuickBooks Online by answering Fiat Lux - ASIA's questions.

Though, you can convert your data from QuickBooks Desktop (QBDT) to QuickBooks Online (QBO). When transferring your file it requires you to convert all your data from the period you're staring using the book. Please refer to this article to get more details about moving your QBDT file to QBO.

Also, you'll want to check this article: What data doesn't convert from QuickBooks Desktop to QuickBooks Online?

If you only want to transfer a particular date, I'd suggest using a web connect . It's a way to bring your transactions to QuickBooks.

But before doing so, you'll have to create a Journal Entry to adjust the beginning balance since moving the data on a particular date will affect the balance. I'll suggest reaching out out to your accountant to help you further with this.

Here are the supported formats to use when importing file to QuickBooks Online:

• Comma-Separated Values (CSV)
• QuickBooks Online (QBO)
• Quicken (QFX)

I'll be right here if you have follow-up questions with QuickBooks.