How to format a CSV for HubSpot import
Get your contact list into a CSV HubSpot imports cleanly the first time: the right columns, dates and phone numbers HubSpot accepts, and no duplicate contacts.
By Operelio team · Updated July 2026
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What HubSpot needs from your file
HubSpot imports a CSV by matching each column to a contact property. The import goes smoothly when your columns line up with HubSpot's properties, your email column is clean, and your dates and phone numbers are in a format HubSpot accepts. Most failed imports come down to one of those three.
HubSpot uses email as the unique key for contacts, so a clean, de-duplicated email column is the single most important thing to get right.
Map your columns to HubSpot properties
Rename your headers so HubSpot can auto-match them, or map them by hand during import. The common contact properties:
| Your column | HubSpot property |
|---|---|
| Email (the unique key for contacts) | |
| First name | First Name |
| Last name | Last Name |
| Phone | Phone Number |
| Company | Company Name |
| Job title | Job Title |
| Website | Website URL |
Any column HubSpot does not recognize can be mapped to a custom property during import, or left out. Decide before you import so you are not creating properties by accident.
Fix the formats HubSpot is fussy about
A few fields cause most import errors:
| Field | Get it right |
|---|---|
| Dates | Use one consistent format, either ISO (YYYY-MM-DD) or your account's date format. Mixed formats in one column are the most common cause of a rejected date. |
| Phone numbers | One consistent format. Keep the country code if you have international numbers. |
| Multiple values | For a multi-select property, separate values with a semicolon. |
| Encoding | Save as UTF-8 so accented names and symbols do not arrive garbled. |
Remove duplicates before you import
HubSpot merges contacts that share an email, so exact duplicates usually collapse on their own. The rows that cause trouble are near-duplicates: the same person with two different emails, or two spellings of one company. Clean those in the file first, where you can see them, rather than after they are in HubSpot.
From messy export to import-ready
Doing it manually means renaming headers to match HubSpot properties, writing formulas to standardize dates and phone numbers, sorting to catch duplicate emails, then saving as CSV UTF-8. It works, but every step is a chance to slip.
The CRM Formatter handles the same work when you pick HubSpot as your target: it maps your columns to HubSpot properties, standardizes the formats, flags duplicates, and hands back a file HubSpot accepts. On Pro and up it can push contacts or companies to HubSpot for you.
Map your columns to HubSpot properties, fix the formats, and download a file HubSpot accepts.
Frequently asked questions
Does HubSpot need a specific date format?
Use one consistent format across the column, either ISO (YYYY-MM-DD) or your account's set format. The usual cause of a rejected date is mixed formats in the same column, not the format itself.
Will importing create duplicate contacts?
HubSpot uses email as the unique key and merges contacts that share one, so exact duplicates collapse. Near-duplicates with two different emails are the ones to clean in your file first.
What CSV encoding should I use?
UTF-8. It keeps accented names and symbols intact so they do not import as garbled characters.
Can Operelio push to HubSpot directly?
Yes, on Pro and up. CRM Formatter can format your file and push contacts or companies straight to HubSpot, with a preview of what will import first.
Ready to get started?
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