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When you import transactions, the template should meet the required format to successfully bring them to your company. QBO uses the 3-column or 4-column template.
If an incorrectly mapped file is uploaded, the option will gray out or you'll receive an error. Review the data and make sure it doesn’t contain any of the information listed in this article. Proceed directly to the Formatting CSV files for import section for the complete list: Import bank transactions using Excel CSV files.
Aside from that, the maximum file size is 350 KB. If your file is too big, shorten the date range and download your transactions in smaller batches. Check out this link for more information: Manually upload transactions into QuickBooks Online.
After configuring the file, you can start transferring the entries and downloading them into QBO. In case you encounter any hurdles, the following guide can help resolve the issue: Common errors for importing bank transactions using CSV.
Visit the Community again if you have any other concerns about QuickBooks. I’ll pop right back in to assist further. Have a good one.