When uploading products via CSV or XLSX, how does quickbooks separates products? Will it separate them by SKU number, or by sales description, or by product name?

Thanks for connecting with us here on the Community page, Nathy1. 

Allow me to share insight about importing transactions using CSV file.

When importing products and services into Quickbooks Online, it will be separated by type and line items. Keep in mind that once you import a list, it can't be undone.

Here's how:

1. Go to the Gear icon. Then select Import Data.
2. Select Products and Services.
3. Select Browse to upload the file from your computer.
4. Choose the file, and then select Open then click Next. 
5. Map your information. Your Field represents the headers on your spreadsheet.
6. Select the one that matches a field in QuickBooks Online from each drop-down then click Next. 
7. Check the cell in your spreadsheet. If you see some cells highlighted in red, this means the cell is invalid. 
8. Select Overwrite all values for each product or service with the same name. Make sure everything looks correct because this can't be undone.
9. Select Import.

For additional reference, you can check this article for the detailed steps on how to import bank transactions using Excel CSV files.

Don't hesitate to leave a comment below if you have additional questions about importing transactions using the CSV files. I'm always ready to assist. 

@Nathy1 

You may prepare the data with the following template

then utilize an importer tool

https://transactionpro.grsm.io/qbo