iCIMS to Workday requires API-based extraction (10K calls/day limit), careful mapping around Workday's CRM gap, and WWS for loading — CSV/EIB can't preserve relationships or attachments at scale.
A technical guide to migrating from iCIMS to Workday — covering API rate limits, data model mapping, the CRM gap, and step-by-step migration architecture.
Read this first
Pair-specific gotchas that catch teams out. Each one has cost somebody a weekend.
Before scoping, verify your Workday tenant's actual CRM capabilities
If your iCIMS instance relies heavily on CRM features — talent pools, nurture campaigns, engagement scoring — budget for a third-party CRM integration alongside the Workday Recruiting migration. Skipping this step is the most common cause of unexpected data loss.
Keep a raw, immutable copy of every source payload you extract from iCIMS
The easiest rollback is not writing delete scripts in Workday — it's being able to replay a known-good source snapshot with corrected mappings.
The Custom Field Trap
iCIMS allows near-unlimited custom fields. Workday heavily restricts custom objects and requires explicit configuration for each. Audit iCIMS custom fields and map them to standard Workday fields wherever possible, or accept that some data stays behind.
iCIMS uses customer-specific custom field IDs, but standard fields have consistent
iCIMS uses customer-specific custom field IDs, but standard fields have consistent integration IDs across all customers. Always map using standard field IDs where possible to ensure repeatability across environments.
To compress a 30-day extraction window, request an API Call Limit Increase from iCIMS
To compress a 30-day extraction window, request an API Call Limit Increase from iCIMS (available in blocks of 10,000). At 50,000 calls/day, extraction drops to approximately 6 days. This is almost always worth the cost for enterprise migrations.
The runbook
Work top to bottom. Tick steps as you go — your progress is saved in this browser.
01 Discovery Scope candidates, pipelines and the compliance obligations that come with them.
Objective Agreed scope across candidates, applications, jobs and interview history, with legal signed up on retention.
Keep these open
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Inventory every object in iCIMS
Count candidates, applications (a candidate can have many), jobs and requisitions, interviews, scorecards, offers, and resume files. Applications and scorecards usually outnumber candidates several times over, and resume files dominate storage.
Data Profiler Get real record counts instead of estimating from memory -
Settle retention and consent with legal
Candidate data is heavily regulated: GDPR right-to-erasure, EEOC/OFCCP record-keeping, and per-region retention windows that conflict with each other. Decide what may be migrated at all before you scope anything else — this frequently shrinks scope substantially.
Migrating candidate records whose consent has lapsed or whose retention window has expired creates a new compliance breach in the target system.
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Map the hiring pipeline and agree the target stages
Document every job's pipeline, stage, and rejection reason, then agree the Workday model with talent leadership. Stage definitions drive every funnel metric you report, so changing them silently rewrites your hiring analytics.
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Catalogue integrations and the job-board estate
List job boards, careers-site integration, HRIS, background check, assessment platforms, calendar and email. The careers site and job boards are customer-facing, so their cutover needs its own plan and its own testing.
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Build the business case and choose the window
Model licence delta, effort and recruiter productivity dip. Time the window against your hiring cycle: a migration during peak graduate recruitment or a hiring surge will fail on people, not technology.
Vendor Evaluator Score Workday against alternatives on weighted criteria
iCIMS → Workday specifics
- Small business (<5,000 candidates)
- CSV + EIB for core data; accept historical data loss
- Enterprise (50,000+ candidates)
- API-based or Custom ETL with managed service support
- Low engineering bandwidth
- Managed migration service — not a low-code sync tool pretending to be a migration engine
- Last N years
- of closed requisitions (e.g., 2 years for compliance, 3 years for operational value)
- CRM data
- migrate to Beamery/Gem, archive to data lake, or discard
Don't move on until
- Counts confirmed for candidates, applications, jobs and offers
- Retention and consent obligations confirmed with legal
- Hiring-stage model agreed with talent leadership
02 Data Audit Audit candidate data with compliance sitting next to you.
Objective Profiled exports with duplicates, expired records and resume files all quantified and triaged.
Keep these open
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Export and profile candidates, applications and jobs
Profile each object separately and reconcile against API counts. Watch the candidate-to-application ratio: a mismatch usually means applications have been silently truncated by pagination.
Data Profiler Profile the iCIMS export for nulls, outliers and type drift -
Quantify duplicate candidates and agree survivorship
The same person applies repeatedly over years with different emails and name spellings. Measure the duplicate rate and agree survivorship rules — which record wins and what happens to the application history attached to the losers.
Merging candidates without agreed survivorship rules destroys application and interview history that you may be legally required to retain.
Data Cleaner Strip empty rows, stray whitespace and dead columns -
Identify records outside their retention window
Flag candidates whose consent has expired, who have exercised erasure, or who fall outside regional retention. Exclude them from scope and document the exclusion — you need to show the decision was deliberate.
PII & Compliance Scanner Find regulated fields before they land in a new system -
Inventory resume files and attachments
Count files, total volume and MIME types, and check every attachment still resolves to a live URL. Expiring signed download URLs are the classic reason a resume migration completes with a large fraction of empty files.
Resume download URLs are often short-lived signed links. Fetch files close to load time or they will 404 mid-migration.
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Verify relationship integrity
Confirm every application links to a live candidate and a live job, and every scorecard to a real interview. Orphaned applications produce a funnel report that does not tie to anything.
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Clean, normalise and produce masked test data
Normalise emails, phone formats and locations, standardise timestamps to UTC, and generate a masked dataset for the sandbox. Real candidate data in a sandbox is a compliance breach in most jurisdictions.
PII Masker Generate a safe copy for sandbox and vendor testing
Don't move on until
- Duplicate candidate rate quantified with a merge policy agreed
- Records outside retention identified and excluded
- Resume and attachment inventory complete with total volume
03 Field Mapping Map the candidate-application-job triangle before anything else.
Objective A signed mapping covering objects, stages, rejection reasons, scorecards and EEO fields.
Keep these open
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Map the candidate, application and job model
ATS platforms differ on whether a person or an application is the primary record. Establish this first: getting it wrong means one candidate becomes five, or five applications collapse into one, and the entire field map has to be redone.
Candidate-centric and application-centric models are not interchangeable. Confirm which Workday uses before mapping any field.
Schema Mapper Match iCIMS fields to Workday by uploading both schemas -
Map pipeline stages and rejection reasons exhaustively
Enumerate every stage and rejection reason across all jobs, including retired values on historical applications, and map each explicitly. Unmapped rejection reasons are both a reporting gap and, in regulated hiring, a compliance one.
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Decide EEO and diversity data handling
These fields are separately regulated and often legally required to be stored apart from the candidate record. Confirm with legal whether they migrate at all, and how Workday isolates them.
EEO data usually cannot be migrated into ordinary custom fields without breaching the segregation rules that govern it.
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Map interviews, scorecards and feedback
Structured scorecards rarely have a native equivalent. Decide whether to reconstruct them, flatten them into notes, or keep them only in the archive — and be explicit that flattening loses the ability to report on them.
JSON to CSV Converter Flatten nested API responses into a reviewable sheet -
Plan resume and file migration
Confirm size limits, MIME support and whether Workday re-parses resumes on upload. Re-parsing can overwrite carefully curated candidate fields with worse machine-extracted values, so test it deliberately.
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Set load order and freeze the spec
Users, then jobs, then candidates, then applications, then interviews and scorecards, then files. Keep source IDs in custom fields, then version and sign off the spec.
Don't move on until
- Candidate/application/job model mapped and reviewed
- Every stage and rejection reason explicitly mapped
- EEO and diversity field handling agreed with legal
04 Test Migration Pilot whole candidate journeys, not isolated records.
Objective A sandbox pilot where candidate journeys, funnel metrics and resume files all verify.
Keep these open
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Configure the Workday sandbox with the agreed pipelines
Create jobs, pipeline stages, scorecard templates, user roles and custom fields first. Loading applications before the stages exist puts every candidate in a default stage and invalidates the pilot.
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Select complete candidate journeys as the pilot slice
Take 100-200 candidates with all their applications, interviews, scorecards and files — including repeat applicants, hires, rejections at every stage, and candidates on multiple jobs. Repeat applicants are where the model mapping actually gets tested.
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Run the load in dependency order with logging
Jobs, candidates, applications, interviews, then files, logging each request against its source ID. Track file uploads separately: they fail for different reasons and at different rates than record writes.
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Verify journeys and funnel metrics
Confirm each candidate sits at the right stage on the right job with their history intact, and that per-stage funnel counts match iCIMS for the pilot jobs. Funnel mismatches point straight back to stage mapping.
Migration Validation Tool Diff the pilot batch against source before scaling up -
Open every pilot resume and check re-parsing
Actually open the files rather than trusting the upload count, and check whether re-parsing has overwritten any candidate fields. A resume that uploaded as a zero-byte file still counts as a success in most logs.
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Put recruiters in front of the pilot data
Have recruiters work their own pilot requisitions end to end. They immediately spot missing feedback, wrong stages and unreadable history that reconciliation cannot see.
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Start small
Load 100 records to catch schema errors early.
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Run at least two full test migrations
before production — one happy-path test and one ugly-data test with edge cases.
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Confirm idempotency
Re-run the migration to verify no duplicate records are created.
iCIMS → Workday specifics
- Always test in Workday Sandbox first
- Never execute a production migration without full sandbox validation. Workday's EIB includes a Validate File Only mode that runs a trial without committing data.
- Scale incrementally
- 100 → 1,000 → 10,000 → full load. Check error rates at each tier.
- UAT with real recruiters
- Have 3–5 recruiters verify their own candidate records, applications, and attachment accessibility. Use live business cases: pick one high-volume requisition, one confidential requisition, one hired candidate with files, and one recruiter-owned talent pool that matters. If those pass, the rest is usually a scale problem, not a logic problem.
Don't move on until
- Candidate-application-job relationships intact for the pilot
- Funnel counts per stage match source for pilot jobs
- Resume files open correctly for every pilot candidate
05 Cutover Switch recruiting without dropping a live candidate.
Objective All in-scope recruiting data live in Workday, careers site and boards repointed, recruiters working.
Keep these open
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Pre-load historical candidates and closed jobs
Load closed requisitions, rejected candidates and archived applications while iCIMS stays live. Only active pipeline and the final delta need to move in the window.
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Publish the runbook including the careers-site switch
A timed sequence with owners and abort criteria, treating the careers site and job boards as first-class steps. They are candidate-facing, so a failure there is publicly visible in a way a data defect is not.
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Freeze iCIMS and take the final delta
Stop new applications and let recruiters finish in-flight actions, then export everything changed since the pre-load. Coordinate with anyone actively interviewing so feedback is not entered into the old system mid-freeze.
Interview feedback entered in the old ATS during the freeze is lost, and it is the data recruiters most immediately notice missing.
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Load active pipeline and reconcile stages
Load active candidates and applications, then verify every active candidate is at the correct stage on the correct job before repointing anything. Active-stage accuracy is what recruiters check first on day one.
Migration Validation Tool Confirm the final delta landed before you reopen -
Repoint careers site, job boards and integrations
Switch the careers-site integration, repost or migrate live job ads, and repoint HRIS, background check, assessment and calendar integrations. Then submit a real test application through the careers site and every major board.
Job ads left posted against the old ATS keep collecting applications that never reach the new system.
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Go/no-go and switch recruiters over
Call the decision against the exit criteria, then move recruiters with support on hand for the first day. Keep iCIMS read-only — candidate records have retention obligations that outlast the migration.
iCIMS → Workday specifics
- Before migration
- Take a full data export of the iCIMS environment (data + attachment archive). Snapshot the Workday Sandbox state.
- During migration
- Log every API call with request/response payloads. Track Workday WIDs mapped to iCIMS source IDs via crosswalk tables.
- If rollback needed
- Use Workday's rescind/cancel operations for loaded business process records. For EIB loads, error reports identify which records failed. The easiest rollback is replaying a known-good source snapshot with corrected mappings.
Don't move on until
- Historical load complete and reconciled before the freeze
- Careers site and job boards posting into Workday and verified
- Active candidates confirmed at the correct stage
06 Validation Prove the funnel, the files and the compliance position.
Objective Reconciled recruiting data, funnel parity with baseline, and a defensible compliance record.
Keep these open
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Reconcile every object including files
Compare counts for candidates, applications, jobs, interviews, scorecards and files, with field-level spot checks on a sample. Count files separately — they are the object most likely to be quietly short.
Migration Validation Tool Reconcile iCIMS and Workday record-for-record -
Tie funnel and time-to-hire reporting to baseline
Rebuild funnel conversion, time-to-hire, source effectiveness and offer-acceptance reporting and compare to pre-migration figures. Variances trace back to stage mapping and to how application timestamps were handled.
Time-to-hire depends on stage-transition timestamps. If those were approximated, the metric will differ even with identical records.
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Verify file integrity at scale
Sample-open resumes across the whole load and compare file sizes against source. Zero-byte and truncated files are common and never surface in an upload success count.
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Confirm retention, consent and EEO configuration
Verify retention rules, consent state and EEO segregation are correctly configured in Workday, and that excluded records genuinely did not migrate. File this as your compliance evidence.
PII & Compliance Scanner Produce the compliance evidence your auditor will ask for -
Test workflow, notifications and candidate-facing paths
Fire every stage automation, interview scheduling flow, rejection template and offer approval, and submit a live application through the careers site. Candidate-facing emails going out wrong is a brand problem, not just a bug.
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Sign off and schedule decommission
Get written acceptance against the Discovery criteria, retain iCIMS read-only for the period your retention policy requires, take a final archive export, and diarise cancellation.
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Rebuild automations
iCIMS workflow triggers, email templates, and status-change automations don't transfer. Rebuild in Workday's Business Process framework.
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Monitor for 30 days
Set up audit reports in Workday to flag candidate records missing critical data. Watch for unmapped values and user-reported issues.
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Keep iCIMS read-only during hypercare
so unresolved exceptions can be replayed or archived.
iCIMS → Workday specifics
- Reconfigure integrations
- Job board postings, background check vendors, assessment tools — all need new connections to Workday's integration layer.
- User training
- Workday Recruiting's UI paradigm differs significantly from iCIMS. Recruiters used to iCIMS's flexible CRM will need role-specific training on Workday's structured, process-driven interface.
- CRM migration (if applicable)
- If moving CRM data to Beamery or Gem, this can run in parallel with or after the core ATS migration.
Don't move on until
- Reconciliation complete across candidates, applications and files
- Funnel and time-to-hire reporting tie to baseline
- Retention and EEO configuration verified, acceptance signed
Field mapping reference
The field-by-field mapping for each object. Use this as the starting point for your mapping spec.
Object Equivalent
| iCIMS field | Workday field | Notes |
|---|---|---|
| Person Profile (Candidate) | Candidate | Name, contact info, source. Custom fields require Workday custom object or calculated field configuration. |
| Person Profile (Employee) | Worker | Only relevant if syncing employee data bidirectionally. |
| Job Profile | Job Requisition | Map title, location, department, posting status. Requisition is tightly coupled to Position and Organization. |
| Recruiting Workflow | Job Application | The join object. Must carry application status, stage history, and disposition. |
| Company Profile / Location | Organization / Location | Workday's supervisory org hierarchy is more rigid than iCIMS's flat company model. |
| Talent Pool Profile | No standard equivalent | Migrate to third-party CRM talent pool, Workday custom object, or archive. |
| CRM Campaigns | No standard equivalent | Migrate to third-party CRM or archive. |
| iForms | No direct mapping | Archive as PDF attachments or extract specific compliance fields into Workday custom objects. |
| Attachments (resumes) | Candidate Attachments | Binary extraction from iCIMS, upload via WWS Put_Worker_Document. |
| Notes / Interview Feedback | Job Application Comments | Workday's comment model is simpler than iCIMS's structured interview feedback. Expect data compression. |
iCIMS Workday
| iCIMS field | Workday field | Notes |
|---|---|---|
| First Name | Legal First Name | Direct map |
| Last Name | Legal Last Name | Direct map |
| Email Address | Validate format; primary email only | |
| Phone | Phone Number | Map phone type (home/mobile/work) |
| Source | Recruiting Source | Picklist value mapping required |
| Resume | Candidate Attachment | Binary transfer, preserve filename |
| Application Status | Application Stage | Map iCIMS statuses to Workday business process stages |
| Job Title | Job Posting Title | Direct map |
| Location | Location | Map to Workday Location reference ID |
| Hiring Manager | Hiring Manager | Map to Workday Worker WID |
| Apply Date | Application Date | Normalize to UTC. Workday defaults to current date if not explicitly set. |
| Custom Fields | Custom Object / Calculated Field | Requires per-field Workday configuration |
Tools used in this playbook
All free, all run entirely in your browser — nothing is uploaded.
FAQ
Can I migrate iCIMS data to Workday using CSV files?
Only for basic, flat data like candidate names and emails. CSV exports from iCIMS flatten nested relationships (Requisition → Candidate → Application chains), drop attachments, and lose CRM/talent pool data. Workday's EIB import caps at 30 MB via browser upload and around 300 MB via SFTP. For enterprise-scale migrations with full-fidelity historical data, API-based extraction is required.
What are the iCIMS API rate limits for data migration?
iCIMS enforces a default limit of 10,000 API calls per day per customer, with approximately 5 concurrent calls per license. Each response includes rate limit headers showing remaining calls and reset time (12:00 AM UTC). Higher limits can be purchased in blocks of 10,000. For 100K+ candidate migrations, budget at minimum 30 days of extraction at default limits.
Does Workday Recruiting have a CRM equivalent to iCIMS?
Not a direct equivalent. Workday's talent acquisition suite includes candidate engagement and marketing features, but iCIMS's full CRM functionality — talent pools, nurture campaigns, SMS outreach, engagement scoring — typically doesn't map one-to-one into Workday. Organizations commonly integrate third-party CRM tools like Beamery or Gem. Verify your specific Workday tenant's capabilities before scoping.
How long does an iCIMS to Workday migration take?
Timeline depends on data volume and method. A small migration (under 5,000 candidates) using CSV/EIB can complete in 1–2 weeks. Enterprise-scale API-based migrations (50,000+ candidates with attachments) typically take 4–8 weeks including test migrations, with the extraction phase alone taking 1–4 weeks depending on API limit increases. Workday implementations themselves average 6–12 months.
What data is most likely to be lost when migrating from iCIMS to Workday?
The most common data loss areas are: CRM engagement history (no standard Workday target), structured interview scorecards (compressed to comments), iForm compliance data (no direct mapping), historical application stage timestamps (Workday may reject backdated transitions), talent pool memberships (require third-party CRM), and files on the iCIMS Attachments tab that lack a field ID and aren't API-accessible.