hello – experiencing the same error.
OnlyOffice 8.2.2 on Mac OS
import different cvs files with a date. preview shows dates just fine. But when I open the file all the dates show as 1/21/1970 no matter what date format I choose. The dates are definitely different in each cell, and when opened in other programs render just fine.
Hello @splatt
We keep working on it. Sorry for inconvenience.
I have the same issue onlyoffice 8.2.2.22 (deb) .
Date is getting changed. On the popup windows it gets recognized right. after confirming settings it gets transformed
should there be some fix or workaround? Thanks in advance
Hello @ilmondodiwit
Please specify how you are inserting this data - is it direct opening of CSV or it is imported via Data tab?
The issue with differences in CSV data upon opening CSV file and importing it is now fixed. Please update your app to the actual version 8.3 and check the situation again.
Hi Team,
With OnlyOffice running at version 9.0.0.172, I thought I would have another look at the Date formatting for CSV import again.
It is also annual taxation reporting time, so dated transaction analysis is the current theme for the coming couple of months 
And I did notice something quite unusual…
This is a screen shot of some raw CSV in a text editor ( Notepad++ )
It is an extract from a Bank transaction download, the date is DD/MM/YYYY format, which is expected from my region.
If I open this file with OnlyOffice, it ends up looking like the following;
The third and fourth lines should be 11 June 2025, but are parsed as 6 November 2025, which is wrong in this context.
However, if I open a blank spreadsheet, then use the menu option Data / Get Data / From Local TXT/CSV to import the CSV file, it ends up looking the following;
The third and fourth lines are being parsed as 11 June 2025.
It is like, once the spreadsheet is open, it is following the regional settings for data format, but not on a direct open operation.
… quite interesting.
I can confirm I’m seeing the same behaviour - opening a CSV file assumes US date format (MM/DD/YY) unless that would make it a nonsense date, then it moves to (DD/MM/YYYY) for that line only. This creates a very obvious problem as you’ve described. I’m also on the version 9 release.
It does seem that OnlyOffice does default to the US date format upon launch, but corrects after launch. But the date parsing is being processed before the correct regional settings are defined within the application.
In my small test, it probably tried to parse all the date data as US format, but a 13th month is not possible, so it was forced to parse those lines as DD/MM/YYYY, but reverted to the US format as soon as the data permitted it.
I can foresee two possible solutions for this; one, do not start import/parsing until the region format is confirmed; or two, have regional format configuration available in the applications settings. The OS knows the regional settings, so the former option would seem to be the logical one.
Hello @DavidRGreen
Thanks for the data. We’ll check this out too. Please await my feedback.