This guide provides an in-depth approach for migrating data from Zendesk Sell to HubSpot CRM. This process relies heavily on the RESTful APIs of both platforms, emphasizing object mapping, sequential migration, and robust handling of associated data and rate limits.
Read this first
Pair-specific gotchas that catch teams out. Each one has cost somebody a weekend.
This guide targets HubSpot CRM API v3 and the Zendesk Sell Core API v2
API behavior may change — always verify against the official documentation linked at the bottom.
Edge case — Contacts without email
HubSpot uses email as the primary deduplication key for contacts. If a Zendesk Contact (person) has no email address, you cannot use the upsert-by-email endpoint. Use batch/create instead and store the returned HubSpot ID. Flag these records for manual review after migration, as they may create duplicates if the same person is later added with an email.
Email and communication history
Zendesk Sell stores email threads tied to contacts and deals. Migrating these is typically the most painful part of any CRM migration. If preserving email history is a requirement, expect to extract email records from Zendesk Sell and recreate them as HubSpot Email engagement objects (POST /crm/v3/objects/0-49) with appropriate timestamps and associations. This is a non-trivial effort that often warrants dedicated handling.
Property group naming
HubSpot lets you create custom property groups via the API or UI. Grouping Service Hub properties by function (classification, context, resolution) prevents the "wall of fields" problem that makes tickets harder to work in practice.
No programmatic export
Zendesk Sell automations cannot be exported via API and recreated in HubSpot programmatically. Every automation rule must be manually documented in the source system, translated to HubSpot's workflow model, and rebuilt. Budget time for this — it is the most labor-intensive part of the Service Hub migration.
The runbook
Work top to bottom. Tick steps as you go — your progress is saved in this browser.
01 Discovery Agree scope, pipeline design and success criteria before touching data.
Objective A scope covering every object in the revenue model, with sales leadership signed up to the pipeline design.
Keep these open
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Inventory every object in Zendesk Sell
Count accounts, contacts, leads, deals or opportunities, activities, notes, emails, files, products and quotes. Activity and email history is usually the largest object by an order of magnitude and the one people forget to size.
Data Profiler Get real record counts instead of estimating from memory -
Map the current pipeline and agree the target model
Document every pipeline, stage, probability and required field, then agree the HubSpot model with sales leadership. Migrating a broken pipeline faithfully is a wasted opportunity; redesigning it mid-migration is a wasted migration.
Stage changes alter historical conversion rates. Agree how you will restate reporting before you change the model.
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Catalogue integrations and automation
List every system touching Zendesk Sell: marketing automation, quoting, billing, ERP, data enrichment, dialler, BI. Each is a separate cutover task with its own owner, and each can silently write bad data into your new CRM.
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Capture the reporting that must survive
Interview the people who actually live in the dashboards — forecast, pipeline coverage, rep activity, cohort conversion. Every one of these needs the underlying fields to migrate, which frequently expands the scope.
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Build the business case and pick the go-live date
Model licence delta, implementation effort and productivity dip. Then choose the date deliberately: mid-quarter is disruptive, quarter-end is worse. Most teams land on the first week of a new quarter.
COI & ROI Calculator Build the 36-month business case you will need for sign-off
Don't move on until
- Object counts confirmed for accounts, contacts, deals and activities
- Target pipeline and stage model agreed with sales leadership
- Reporting requirements captured from the people who use the reports
02 Data Audit CRM data is usually dirtier than anyone expects. Find out how dirty.
Objective A profiled export with duplicates, ownership gaps and relationship integrity all quantified and triaged.
Keep these open
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Export and profile every object
Profile null rates, distinct values and type consistency across all objects. Pay attention to fields sales reps were supposed to fill in: an 80% null rate on a field your forecast depends on is a business finding, not a data one.
Data Profiler Profile the Zendesk Sell export for nulls, outliers and type drift -
Quantify duplicates and agree the merge policy
Measure duplicate accounts (same company, different spellings and suffixes) and contacts (same email, or same person at a renamed company). Agree survivorship rules before merging: which record wins, which fields, and what happens to the activity history on the loser.
Merging before you have agreed survivorship rules destroys history irreversibly. Decide first, merge second.
Data Cleaner Strip empty rows, stray whitespace and dead columns -
Verify relationship integrity
Check every deal has a valid account, every contact a valid account, every activity a valid parent. Referential breaks are the defect that turns a clean-looking load into a CRM where the pipeline report does not tie to the account list.
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Resolve ownership and the user map
Build the Zendesk Sell user → HubSpot user map, including leavers. Every record needs a valid owner: records assigned to deactivated users either fail to load or land unassigned, and unassigned pipeline is pipeline nobody works.
Records owned by deactivated users are a top cause of load failures. Decide the reassignment target before you start.
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Scan for PII and regional compliance
CRMs hold marketing consent, lawful basis and unsubscribe state. Confirm these fields migrate intact and that consent provenance survives — losing consent records is a regulatory problem, not a data-quality one.
PII & Compliance Scanner Find regulated fields before they land in a new system -
Clean, normalise and archive the pre-state
Normalise country and state values, phone formats, currencies and casing, and standardise all timestamps to UTC. Keep an untouched copy of the raw export — it is your only reference if a mapping decision turns out wrong.
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Batch APIs
Utilize HubSpot's batch endpoints for creation, reading, and updating whenever possible. For example, batch operations for contacts are limited to 100 records per request.
Zendesk Sell → HubSpot specifics
- Standard Limits
- Depending on the HubSpot subscription tier, the limit can range from 100 to 190 requests per 10 seconds per app (for Professional/Enterprise tiers, it may be 150 requests/10 seconds for association APIs). Daily limits also apply (e.g., 625,000 to 1,000,000 requests per day for Professional/Enterprise).
Don't move on until
- Duplicate rate quantified per object with a merge policy agreed
- Every record has a valid owner mapped to a target user
- Relationship integrity verified — no orphaned deals or contacts
03 Field Mapping Map objects, relationships and picklists — in that order.
Objective A signed mapping spec that covers objects, relationships, picklist values and currency handling.
Keep these open
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Map objects and their relationships first
Establish how Zendesk Sell objects correspond to HubSpot objects before any field work. Leads-versus-contacts, accounts-versus-organisations and deal hierarchies differ structurally between CRMs, and a field map built on the wrong object model has to be redone.
Schema Mapper Opens pre-loaded with the Zendesk Sell → HubSpot field pair -
Generate and then hand-review the field map
Auto-match both schemas, then review every row. Look hardest at anything named "type", "source", "stage" or "status", where names match and meanings do not.
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Map every picklist value, including retired ones
Enumerate all values on both sides — deal stages, lead sources, industries, statuses — and map each explicitly, including values no longer offered but still present on old records. Unmapped values either fail the row or land as blanks that quietly break segmentation.
Historical records often carry picklist values that were retired years ago and no longer appear in the UI.
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Decide currency, amount and date handling
If you sell in multiple currencies, confirm how HubSpot stores amounts, exchange rates and dated conversion rates. Recalculating historical deal values at today's rate silently rewrites your revenue history.
Multi-currency deals re-converted at current rates will not tie to your historical reporting or your finance system.
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Determine the load order
Sequence the load so parents exist before children: users, then accounts, then contacts, then deals, then activities and notes. Keep source IDs in custom fields so relationships can be rebuilt by lookup rather than guesswork.
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Freeze the spec and sign off
Version-control the mapping, walk RevOps and sales leadership through the decisions that change reporting, and get written sign-off before the pilot.
Don't move on until
- Object and relationship model mapped and reviewed
- Every picklist value explicitly mapped, including dead values
- Load order determined so parents always exist before children
04 Test Migration Pilot with related records, not a flat sample.
Objective A pilot load whose relationships, ownership and roll-up reporting all verify against source.
Keep these open
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Configure the HubSpot sandbox to match the agreed model
Build the pipelines, stages, custom fields, record types and user roles first. Load into a default configuration and you will only discover the configuration defects at full scale.
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Select a connected pilot slice
Take complete account trees — 50-100 accounts with all their contacts, deals, activities and files — rather than a flat random sample. Relationship defects are the whole point of a CRM pilot and a flat sample cannot expose them.
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Run the load in dependency order with full logging
Load users, accounts, contacts, deals, then activities, logging every request against its source ID. Note which failures are transient (rate limits, timeouts) and which are structural (validation, missing parent).
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Verify relationships and roll-ups
Confirm every deal sits on the right account with the right owner and stage, and that pipeline totals per account and per rep match Zendesk Sell exactly. Roll-up mismatches almost always mean a relationship or currency defect upstream.
Migration Validation Tool Diff the pilot batch against source before scaling up -
Measure throughput and project the full load
Record actual records-per-hour under HubSpot's API limits and extrapolate, remembering activity history usually dominates volume. If the projection exceeds your window, split the load or trim activity scope now.
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Let reps work the pilot data
Put two or three reps in the sandbox against their own accounts. They spot missing context, wrong owners and unusable notes far faster than any reconciliation script, and their buy-in is what makes adoption work.
Don't move on until
- Relationships intact across the whole pilot slice
- Pipeline roll-ups match source for the pilot accounts
- Reps have worked pilot records and confirmed they are usable
05 Cutover Switch the revenue system with the pipeline intact.
Objective All in-scope CRM data live in HubSpot, integrations repointed, and reps selling on day one.
Keep these open
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Pre-load history ahead of the freeze
Load closed deals, historical activities and inactive accounts while Zendesk Sell stays live. Only open pipeline and the final delta need to move inside the window.
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Publish the cutover runbook
A timed sequence with owners and abort criteria: freeze, final export, delta load, integration switch, smoke test, go/no-go, rep enablement. Pick a window that avoids quarter-end and month-end close.
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Freeze Zendesk Sell and take the final delta
Set Zendesk Sell read-only and export everything changed since the pre-load. Reps updating deals during an unenforced freeze is the classic way to lose the most recent — and most valuable — pipeline changes.
A rep who updates a deal in the old CRM during the freeze will lose that update permanently.
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Load the delta and reconcile the pipeline
Run the delta, then verify open pipeline value and count per rep against Zendesk Sell before anything else. If the pipeline number is wrong on day one, reps stop trusting the system and never fully come back.
Migration Validation Tool Confirm the final delta landed before you reopen -
Repoint every integration and verify with real records
Switch marketing automation, quoting, billing, enrichment, dialler and BI connections, then push a live record through each path. An unrepointed integration writing into the old CRM causes divergence that gets harder to reconcile every day.
Two-way integrations left pointing at the old CRM will keep writing there. Disable them before you switch, not after.
Cron Expression Builder Schedule the delta syncs that run through the freeze -
Go/no-go, then enable the reps
Call the decision explicitly against the exit criteria. Run enablement on real data with their own accounts on screen, and keep Zendesk Sell read-only rather than cancelled until validation closes.
Zendesk Sell → HubSpot specifics
- Initial Freeze
- Coordinate a period where sales activity is temporarily paused in Zendesk Sell.
- Delta Sync
- Use the updated_at timestamps recorded during the initial bulk export from Zendesk Sell (available on almost all Zendesk objects) to fetch only records updated since that time.
- Upsert to HubSpot
- Use HubSpot's batch upsert endpoints (POST /crm/v3/objects/{objectType}/batch/upsert) for Contacts, Companies, and Deals using unique identifiers (like email or domain) to efficiently update existing records or create new ones in one call.
Don't move on until
- Historical load complete and reconciled before the freeze
- All integrations repointed and verified end to end
- Reps logged in with pipeline visible and correct
06 Validation Prove the revenue numbers tie out, then close the project.
Objective Reconciled data, forecast parity with pre-migration reporting, and signed acceptance.
Keep these open
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Reconcile every object
Compare counts and values across accounts, contacts, deals, activities and files, plus field-level spot checks on a random sample. Produce a single report suitable for audit and for finance.
Migration Validation Tool Reconcile Zendesk Sell and HubSpot record-for-record -
Tie the pipeline and forecast to baseline
Rebuild forecast, pipeline coverage and win-rate reporting and compare to pre-migration figures. Every variance needs an explanation — most trace back to stage or currency mapping decisions made in Field Mapping.
Stage-model changes will legitimately shift historical conversion rates. Restate the baseline rather than chasing the difference as a defect.
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Verify ownership, visibility and permissions
Confirm every record has the right owner and that sharing rules, territories and role hierarchy give each rep exactly the visibility intended. Over-broad visibility in a CRM is a data-protection issue as much as a config one.
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Re-profile for field completeness
Compare loaded null rates against the source profile per field. A field that arrived empty while counts matched is the failure counts alone cannot detect.
Data Profiler Prove field completeness held up through the load -
Test automation and integration write-back
Fire every workflow, assignment rule, sequence and notification, and confirm each integration writes correctly in both directions. Automation is rebuilt rather than migrated, so it is unproven until observed.
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Sign off and schedule decommission
Get written acceptance against the Discovery criteria, keep Zendesk Sell read-only for 30-90 days with a final archive export taken, then diarise cancellation so the contract does not auto-renew.
Zendesk Sell → HubSpot specifics
- Count Verification
- Compare the total count of key entities (Contacts/Persons, Companies/Organizations, Deals, Line Items) between Zendesk Sell and HubSpot.
- Spot Checks
- Perform manual spot checks on complex records (e.g., deals associated with multiple contacts, several activities, and products) to ensure all links and property values were correctly transferred and mapped.
- Association Integrity
- Verify crucial relationships using the HubSpot Associations API. For example, check a sample of Contact records to ensure they are correctly associated with their primary Company.
Don't move on until
- Full reconciliation report complete across all objects
- Forecast and pipeline reports tie to pre-migration baselines
- Acceptance signed and Zendesk Sell decommission scheduled
Field mapping reference
The field-by-field mapping for each object. Use this as the starting point for your mapping spec.
Object (Source) CRM Object (Target)
| Zendesk Sell field | HubSpot field | Notes |
|---|---|---|
| Contact (is_organization: true) | Company | Map Zendesk name to HubSpot name and/or domain. Domain is the recommended primary unique identifier in HubSpot. |
| Contact (is_organization: false) | Contact | Map Zendesk first_name, last_name, and email to HubSpot contact properties. Email is the recommended primary unique identifier. |
| Lead | Lead | Requires association with an existing Contact (Person). Note: Zendesk and HubSpot conceptualize leads differently — in Zendesk Sell, a Lead is a standalone pre-qualified record, while in HubSpot, a Lead object must be associated with an existing Contact and represents a lifecycle qualification status. |
| Deal | Deal | Map pipeline, stages, and financial data. |
| Pipelines & Stages | Pipelines & Stages (e.g., for Deals) | Map likelihoods/probabilities for stages. |
| Product | Product | Requires name, price, hs_sku. |
| Order & Line Item | Order & Line Item | Zendesk Line Items link products to an Order, which is associated with a Deal. HubSpot Line Items are created and linked directly to the Deal or Order. |
| Call | Call (Activity) | Must be logged with an hs_timestamp. |
| Text Message | Communication (Activity) | Logged using hs_communication_channel_type (SMS, WHATS_APP, LINKEDIN_MESSAGE) and hs_timestamp. |
| Note | Note (Activity) | Requires hs_timestamp. |
| Task | Task (Activity) | Requires hs_timestamp. Must be associated with a Contact, Deal, or Lead. |
| Tags | Custom Property (multi-select) | Zendesk Sell supports tags on Contacts, Leads, and Deals. Create a multi-select custom property in HubSpot (e.g., zendesk_tags) and map tag values as options. |
| Custom Fields | Custom Properties | Must be created in HubSpot prior to data import. |
Type Property Type
| Zendesk Sell field | HubSpot field | Notes |
|---|---|---|
| string | Single-line text | Direct mapping. |
| text | Multi-line text | Direct mapping. |
| number | Number | Direct mapping. |
| bool | Single checkbox | Direct mapping. |
| list | Dropdown select | Recreate option values in HubSpot before importing data. |
| address | Multiple single-line text properties | Lossy transformation — Zendesk stores address as a composite object (line1, city, state, zip, country). Create separate HubSpot properties for each component. |
| date | Date picker | Direct mapping. |
| datetime | Date picker | HubSpot date properties do not store time; time component is lost. |
Service Hub Cus m Field Mapping Reference
| Zendesk Sell field | HubSpot field | Notes |
|---|---|---|
| Category / Type (list) | Custom dropdown (e.g., ticket_category) | Recreate all option values before import. |
| Priority (list) | hs_ticket_priority (built-in) or custom dropdown | HubSpot has a built-in priority property — use it if the values align; create a custom property if they don't. |
| Tags (array) | Custom multi-select (e.g., zendesk_ticket_tags) | Same pattern as CRM tag migration in Step 4. |
| Custom text fields (string/text) | Single-line or multi-line text | Direct mapping per Section 1.2. |
| Custom date fields (date/datetime) | Date picker | Time component lost on datetime fields (same caveat as Section 1.2). |
| Custom number fields (number) | Number | Direct mapping. |
| Custom boolean fields (bool) | Single checkbox | Direct mapping. |
Tools used in this playbook
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