Notion Import From CSV Creates Wrong Property Types: Fix

When you import a CSV file into a Notion database, the resulting property types often do not match what you expect. For example, a column containing numbers may become a text property, or a date column may import as a plain text field. This happens because Notion’s CSV import tool automatically guesses the property type based on the first few rows of data, and its guesses are sometimes incorrect. This article explains why Notion misinterprets CSV columns and provides a reliable method to fix the property types after import.

Why Notion Assigns the Wrong Property Type During CSV Import

Notion’s CSV import engine reads the first 100 rows of your file to detect the data type for each column. If a column has mixed formats — for example, most rows contain numbers but a few contain text like “N/A” — Notion defaults to the text property type. Similarly, if a date column contains inconsistent date formats such as “2024-01-15” in some rows and “Jan 15, 2024” in others, Notion may treat the entire column as text. The import tool also cannot handle empty cells gracefully; a column with many blank rows may be imported as text even if the filled cells contain numbers or dates. This automatic type detection is the root cause of the problem. After import, you must manually correct each property type using Notion’s database property editor.

What Happens During the Import Process

When you drag and drop a CSV file onto a Notion page or use the Import button, Notion scans the file and creates a new database. It assigns each column a property type based on its heuristic. The original CSV column headers become the property names. Notion does not let you preview or override these type assignments before the import completes. You only see the results after the database is created. If the types are wrong, you cannot re-import the same file without first deleting the database. Instead, you must edit the properties directly.

Steps to Correct Property Types After CSV Import

The following steps assume you have already imported the CSV and the database exists in your workspace. You will change each property type from its incorrect assignment to the correct one.

1. Open the imported database
   Navigate to the page where Notion created the database. Click the database title to open it in full-page view so you can see all properties.
2. Identify the column with the wrong property type
   Look at the column header in the table view. Each header shows the property name followed by the property type icon. For example, a text property shows a capital “T” icon, a number property shows “123”, and a date property shows a calendar icon. Find the column whose icon does not match the data it contains.
3. Open the property editor
   Click the down arrow next to the property name in the column header. A dropdown menu appears. Select Edit property from the menu. The property settings panel opens on the right side of the screen.
4. Change the property type
   In the property settings panel, click the current type name (for example, “Text”) to open the type selector. Choose the correct type from the list: Number, Date, Select, Multi-select, Email, Phone, URL, or another option. Notion will attempt to convert existing values to the new type. If conversion fails for some cells, those cells will show an error or remain empty.
5. Repeat for each incorrect property
   Go through every column in the database. Change each property type to match its data. Pay special attention to columns that you expected to be dates, numbers, or select options.
6. Verify the converted data
   After changing the type, scroll through the rows to confirm that values converted correctly. For number columns, check that numeric values appear without extra text. For date columns, ensure dates display in Notion’s standard format. If a column contains options, verify that each entry is a single select or multi-select value as intended.

Fixing a Column That Should Be a Select or Multi-Select

If your CSV column contained a list of categories such as “High, Medium, Low,” Notion may import it as text. To convert it to a select property, follow the same steps above but choose Select or Multi-select from the type selector. After conversion, Notion will create each unique value as an option in the select menu. You can then color-code or reorder the options by opening the property settings and clicking the options list.

Fixing a Column That Should Be a Date

Date columns are particularly prone to import errors. If Notion imported your date column as text, change the property type to Date. Notion will try to parse the text into a date. For this to work, the text must be in a recognizable date format such as YYYY-MM-DD or MM/DD/YYYY. If some rows contain dates in a different format, those rows will show an error. You can manually edit those cells after the type change.

If Notion Still Has Issues After the Main Fix

Converted Number Column Shows Blank Cells

If you change a text column to number and many cells become blank, the original CSV data likely contained non-numeric characters such as currency symbols, commas, or spaces. For example, “$1,234.56” will not convert cleanly. To fix this, delete the imported database and prepare the CSV file by removing all non-numeric characters from number columns. Use a spreadsheet editor like Excel or Google Sheets to clean the data, then re-import.

Date Column Shows “Invalid Date” After Type Change

When Notion cannot parse a date string, it displays “Invalid Date.” This happens when the CSV contains dates in multiple formats or uses a format Notion does not recognize. The only reliable fix is to standardize all dates in the CSV to the ISO format YYYY-MM-DD before re-importing. If the database already contains many rows, you can export the database as CSV, edit the dates in a spreadsheet, delete the original database, and re-import the corrected file.

Select Options Are Duplicated or Missing

If your CSV column had slight variations like “High” and “high,” Notion may create two separate select options. After converting the property to Select or Multi-select, open the property settings and merge duplicate options by clicking the three-dot menu next to each option and choosing Merge with…. Alternatively, you can delete the extra option and manually reassign the values.

CSV Import Methods Compared: Direct Import vs Pre-Processing

Item	Direct CSV Import	Pre-Processed CSV Import
Description	Import the raw CSV file directly into Notion	Clean and format the CSV in a spreadsheet before importing
Property type accuracy	Low — Notion guesses types and often chooses text	High — consistent data helps Notion detect the correct type
Time required	Fast — import takes seconds	Moderate — cleaning may take 10-30 minutes
Post-import fixes needed	Almost always required for dates and numbers	Rarely needed if data is uniform
Best for	Small files with simple text data	Any file with dates, numbers, or select options

After reading this article, you can now fix property types in any Notion database created from a CSV import. The next time you import a CSV, prepare the file by standardizing number formats and dates to reduce conversion errors. As an advanced tip, use Notion’s Database templates to pre-define property types before importing: create an empty database with the correct schema, then use the Merge with CSV workflow via a tool like Zapier or a custom script to map columns directly.