Data cleaning for CRM imports
HubSpot import errors
Fix "could not parse date" on a HubSpot import
This error means HubSpot could not read a value in a date property because it is not in a format HubSpot recognizes, or the date format you picked during import does not match the file. The usual cause is a column of ambiguous or mixed dates, not a single bad row. The fix is to standardize the whole column to one clear format, then pick the matching format in the import step so the two agree.
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What the error looks like
A UK-format file is the classic trigger, because 05/07/2026 means the 5th of July when it is written day first, but HubSpot reading it month first turns it into the 7th of May or rejects it outright.
Why it happens
- Day and month order is ambiguous. 07/05/2026 could be the 7th of May or the 5th of July, and dd/mm versus mm/dd guesswork bites UK dates hardest.
- Text month names. A value like "May 7, 2026" is text, not a date HubSpot can read.
- Excel turned the date into a serial number. When a cell loses its date formatting, Excel exports the raw count of days (like 45784) instead of a date.
- The import date-format selector is set wrong. If the format you pick in the HubSpot import step disagrees with what is actually in the file, values fail to parse even when they look fine.
The manual fix
- Standardize the column to one clear format. YYYY-MM-DD is unambiguous, because there is only one way to read 2026-07-05.
- Choose the matching date format in the HubSpot import step, so the format you selected and the values in the file agree.
The Sift fix
- Drop your CSV or Excel file into Sift. It standardizes the whole date column to an unambiguous format like YYYY-MM-DD in one pass.
- Sift converts Excel serial numbers like 45784 back into real dates automatically.
- It previews the ambiguous rows, the ones where day and month are both 12 or under, so you decide once for the whole file instead of guessing row by row.
- Review every change with a diff, then export the cleaned file and import it, picking the matching date format in HubSpot.
What Sift can't fix
Honesty matters here: if a single cell is genuinely ambiguous and has no other clue, like a lone 04/05/2026 with nothing else to disambiguate it, Sift shows it to you to decide rather than guessing. And Sift cleans the file, not the import wizard, so you still pick the matching date format in HubSpot's import step yourself.