Migrate HubSpot to Attio Without Losing Deal History

The moment teams decide to leave HubSpot is almost always the same. Someone opens the billing page, sees the renewal quote for Sales Hub Professional, and realizes they’re paying $500 or $900 per month for a contact database and a handful of automations they could replace with a purpose-built relational CRM for a fraction of the cost. That’s when I get the call. I’ve run this migration for four B2B SaaS clients in the last 18 months, and the thing that trips every team up is not the export step. It’s the assumption that “deal history” means the same thing in both systems. It does not.

Before you migrate

The biggest data loss I see happens before the migration even starts. Teams export too late and miss records that were modified during the cleanup window. Lock your HubSpot instance into read-only mode for reps the day you start exporting. This is not official functionality; just pull admin access from non-owners so nobody is creating deals or updating contacts while you are pulling data.

Run these exports in HubSpot before touching Attio:

• Contacts (all properties, not just defaults): Settings > Data Management > Import/Export > Export contacts. Include lifecycle stage, owner, create date, and last activity date.
• Companies: Same path, export with associated contact count and industry/size fields.
• Deals: Export deal name, pipeline, stage, close date, amount, associated company, associated contact, and create date. HubSpot’s deal export does not include stage change history by default. You need to go to Reports > Analytics > Deal Stage Funnel and export that separately as a report.
• Notes and activities: Export from Contacts > Activity, filtered by type. These come out ugly and need manual cleanup.
• Workflows: There is no export. Screenshot or document every active workflow before you touch anything. I use Loom to record a walkthrough of each one.
• Sequences: Same situation, no export. Log every sequence name, step count, delay, and email body in a Google Sheet.

Also check your HubSpot integrations panel. If you have live syncs running to tools like Salesforce, Outreach, or Gong, pause those syncs before exporting. Mid-write records produce dirty data that is genuinely painful to clean later.

What breaks and what does not transfer

This is the section most migration guides skip. It’s also where I spend the most client time. Don’t skim it.

What transfers cleanly: Contact names, emails, phone numbers, company names and domains, deal names, deal amounts, close dates, pipeline stages (if names match exactly), and custom properties that you pre-created in Attio’s data model.

What does not transfer at all: HubSpot email send history from Sequences, meeting booking logs from HubSpot Meetings, any data captured by HubSpot’s tracking pixel or form submissions that only lived in the activity feed, workflow enrollment history, and A/B test results from email campaigns.

What transfers badly: Notes. HubSpot exports notes as a flat text dump with timestamps jammed into a single column. You can import these into Attio as a note attribute on contact records, but you lose threading and the association to specific deals. My standard call here is to import the last 90 days of notes and archive the rest in a shared Google Doc linked from the deal record.

In HubSpot:
Reports > Analytics Tools
> Deal Stage Funnel Report
> Export as CSV

Columns to keep:
- Deal ID
- Stage name
- Date entered stage
- Date exited stage
- Days in stage

Import these as a custom
"Stage History" note object
in Attio or store in a
Google Sheet linked to
each deal record.

According to HubSpot’s own export documentation, activity data exports are limited to a rolling window and do not include all associated object data in a single file. That is exactly why the multi-pass export approach above is necessary, not optional.

Verify it worked

Before you cancel HubSpot, run these four checks:

1. Deal count parity: Total deals in Attio matches total deals exported from HubSpot (filter to “all time” in both).
2. Owner assignment: Pick 10 random deals in Attio and confirm the assigned owner matches what HubSpot showed. Owner import fails silently if the email address in your CSV does not match an Attio workspace member.
3. Pipeline stage distribution: Deal count per stage in Attio matches your HubSpot funnel report snapshot.
4. Email capture going forward: Send a test email to a contact in Attio from your connected Gmail account and confirm it appears in the contact’s activity feed within 5 minutes.

Keep HubSpot running in read-only mode for 30 days after go-live. Do not cancel the subscription until you have closed at least one deal entirely within Attio and confirmed that the activity log looks correct. Thirty days feels conservative until you actually need it.

HubSpot or Attio: who should switch

Choose Attio if

• Your team is under 25 seats and tired of paying HubSpot's per-feature tax on things like custom reports and sequences
• You want a relational data model where people, companies, and deals connect without manual association hacks
• You are routing enrichment and outreach through Clay or n8n and need a CRM with a clean API, not a marketing suite

From $34/seat/month (Plus) Try Attio →

Choose HubSpot if

• You rely on HubSpot Marketing Hub for email campaigns, landing pages, and ad attribution and cannot separate CRM from marketing
• Your team uses HubSpot's built-in sequences and meeting booking heavily and does not want to re-platform those workflows
• You have more than 50 seats and the migration cost in rep downtime outweighs the subscription savings

From $20/seat/month (Starter) Stay on HubSpot →

If you are also evaluating Pipedrive as an alternative landing spot, our breakdown of what Pipedrive actually costs in 2026 is worth reading before you commit. And if your HubSpot workflows include lead scoring automation, the Trigify + HubSpot lead scoring guide covers what you would be giving up and what you can replicate elsewhere.

For rebuilding outbound sequences post-migration, I’ve had good results routing Smartlead through n8n to push replies back into Attio as deal activities. The pattern is nearly identical to the Smartlead-to-HubSpot sync guide but with Attio’s API endpoint swapped in.

One week before go-live

The migration itself is not the risk. The transition period is. I always run a parallel two-week sprint where reps log deals in both systems, then compare at the end. It sounds tedious, and reps will complain loudly, but it catches field mapping errors that a static record count never surfaces. By the end of week two, every active deal should have matching data in both systems. Then you cut over, put HubSpot in read-only mode, and do not look back.

The Attio API documentation is genuinely good for custom field creation and bulk record writes via REST if you want to automate parts of the import rather than grind through the CSV UI. If your deal count is above 5,000, read it before you start. The CSV approach works fine at lower volumes; above 5,000 records you will want the API for the import itself and for any post-import patching on association errors.