ATS Migration Checklist: How to Move From One Hiring System to Another Without Losing Candidates

Use this ATS migration checklist to move from one hiring system to another without losing candidates, breaking reports or deleting records you still need.

A good migration covers five jobs: audit the old ATS, choose what to move, map workflows, test the import, and cut over safely. The hard part is usually not the import file. It is preserving context.

Candidate records, jobs, applications, attachments, scorecards, notes, offer history and compliance settings all connect to each other. If those relationships break, recruiters lose the story of what happened and hiring managers stop trusting the new system.

This guide uses Breezy HR, Ashby and Greenhouse as vendor examples because they suit different migration shapes. Breezy HR is the SMB-friendly example, Ashby is the scaling and analytics-heavy example, and Greenhouse is the enterprise structured-hiring benchmark.

What is an ATS migration?

An ATS migration is the move of recruiting data and operating workflows from one applicant tracking system to another. That includes the records you can see, plus the rules and settings that make the hiring process work.

At minimum, review candidates, jobs, applications, resumes, attachments, interview activity, scorecards, notes, offers, rejection reasons, source tags, automations, integrations, reports, retention settings and privacy settings. Moving only names and email addresses is quicker, but it usually leaves recruiters without the history they need.

A CSV import can be useful for basic candidate lists. The limitation is that it may not preserve the relationship between one candidate, several applications, interviews, feedback, attachments and compliance records.

That matters because hiring teams rarely search only for a person. They search for why someone was rejected, who interviewed them, whether consent exists, and whether a late-stage candidate still needs feedback.

Which type of ATS migration do you need?

Choose the migration type before you export anything. The right answer depends on hiring volume, reporting needs, compliance obligations and how much old data recruiters still use.

A full historical migration is best if you need long-term reporting, searchable archives and continuity across requisitions. It gives the richest record, but it takes more mapping, testing and vendor support.

An active-candidate-only migration suits teams that need a fast operational cutover. The catch is that the old ATS must remain accessible as an archive until retention, reporting and legal-hold checks are complete.

A CSV or import-only migration works for basic lists, talent pools and small moves. It is risky if lifecycle history matters, because scorecards, interview notes, stage changes and attachments may not travel cleanly.

Starting fresh while archiving the old ATS can be reasonable for a small team with low historical value. Do not choose it until a compliance owner has reviewed retention rules, legal holds and export requirements.

Use API or vendor-assisted migration when relationships need to stay connected. That usually means candidates, jobs, applications, notes, attachments, scorecards, offers and audit history must arrive as linked records, not loose files.

ATS migration checklist by phase

Start with ownership. Assign a project owner, define the go-live date, confirm old and new contract dates, and write a rollback plan before recruiters touch the new system.

Audit the old ATS next. Count open jobs, active candidates, archived candidates, duplicate profiles, sources, tags, attachments, notes, scorecards, offers and reports that the business still relies on.

Run the compliance review before deleting or excluding anything. This is slower than a simple cleanup, but it reduces the risk of removing hiring records you were required to keep.

Map old fields to the new ATS. Cover stages, statuses, rejection reasons, source values, departments, locations, hiring teams, custom fields, consent fields and reporting categories.

Decide how to handle rich history. Resumes, signed offers, scorecards, interviewer notes, email history and activity logs may need different treatment from ordinary profile fields.

Configure the new ATS before import. Set up departments, teams, jobs, stages, scorecards, permissions, templates, automations, careers pages, integrations and compliance settings first.

Run a test import with representative records. Include a simple applicant, a duplicate, a late-stage candidate, a rejected candidate, a candidate with attachments and a candidate with sensitive fields.

Validate field accuracy, record relationships, attachments, search results, permissions and reports. A small test import costs time, but it is cheaper than fixing thousands of broken records after go-live.

Run both systems in parallel long enough to confirm active hiring works. Test interview scheduling, notifications, job board feeds, recruiter workflows, integrations and hiring-manager access.

Before final import, freeze changes in the old ATS. Then run the final delta export, import the last changes, and document any records that could not be moved.

Cut over careers pages, job postings, email templates, calendar links, HRIS connections, background-check tools, analytics, SSO and user access. Train recruiters, hiring managers, interviewers, admins and executives on the workflows they actually use.

Decommission the old ATS only after validation is complete. Keep access until retention, legal hold, export and archive requirements are satisfied.

What data should you migrate?

Build a data object inventory before export. For each object, record whether it migrates, the source owner, the destination field, the transformation rule, the validation sample and any unresolved issue.

Include candidates, applications, jobs, departments, locations, hiring teams, pipeline stages, rejection reasons, sources, tags, attachments, resumes, scorecards, interview feedback, offer records, consent fields, EEO data and reporting fields.

Relational objects need extra care because one candidate can link to several jobs, interviews, notes and compliance records. If those links break, the data may import successfully but still fail operationally.

Be strict about transformation rules. If the old ATS has eight rejection reasons and the new ATS has four, decide which values merge and how historical reporting will interpret them.

Do the same for source tracking. A messy mix of LinkedIn, LinkedIn Recruiter, LI and LinkedIn paid may look harmless, but it can ruin source reporting after migration.

Do not assume attachments are easy. Resumes, offer letters and interviewer documents often sit in different storage locations, and some vendors treat them differently from structured profile fields.

What compliance checks matter before an ATS migration?

Preserve hiring-related records according to the rules that apply to your organisation before deleting, anonymising or excluding data. This guide is a checklist, not legal advice, so confirm obligations with counsel or a compliance owner.

EEOC rules say employers must keep personnel or employment records for one year. Application forms and other hiring-related records must also be preserved for one year after the record was made or the personnel action was taken, whichever is later.

If an applicant or employee files a discrimination charge, relevant records must be maintained until the case is concluded. That means a routine archive cleanup can become risky if legal holds are not checked first.

Federal contractors need extra care. EEOC guidance notes that Department of Labor rules extend retention to two years for federal contractors with at least 150 employees and a government contract of at least $150,000.

For GDPR-covered candidates, check lawful basis, transparency, data-subject rights and storage limitation. The practical migration task is to preserve or remap consent, privacy-notice, deletion, anonymisation and retention settings.

Do not move sensitive fields blindly. EEO, disability, veteran status, background-check data and consent records should have clear permissions and reporting rules in the new ATS.

How do you migrate active candidates without losing momentum?

Treat active candidates as a separate workstream. Historical archives matter, but active candidates affect interviews, offers, recruiter workload and candidate experience this week.

Before go-live, confirm each active candidate's job, stage, owner, next step, scheduled interviews, pending feedback, attachments and communication status. This is manual work, but it prevents the most visible migration failures.

Preserve the last touch and next action for every priority candidate. A profile that imports without the latest recruiter note may look complete, yet still leave the team unsure what to do next.

Send internal communications before the cutover. Recruiters need to know when the old ATS freezes, hiring managers need to know where to submit feedback, and interviewers need working calendar links.

Late-stage candidates deserve the first spot-check after go-live. Verify interview loops, offer approvals, compensation notes, pending scorecards and owner assignments before checking cold archives.

Keep a short exception log. If five candidates could not migrate cleanly, name them, assign an owner and record the next action outside the ATS until the record is fixed.

Vendor examples: Breezy HR, Ashby and Greenhouse

Breezy HR is the clearest small-business example if you want a capable ATS without per-seat fees. ATSLab records Breezy HR at $157, ranking first in our fixed index, but migration help is tied to specific annual plans and source systems.

Breezy's paid public plans are Startup at $157/month, Growth at $273/month and Business at $439/month when billed annually. Its Free Forever Bootstrap plan covers unlimited users and unlimited candidates, but candidate access is limited to candidates added in the last 30 days.

Breezy offers free migration from JazzHR, Workable, Greenhouse or Lever for eligible customers up to 25,000 candidate records. Above 25,000 records, Breezy charges a one-time fee starting at $250 based on total candidate records.

The catch is eligibility. Breezy migration is available only on annual Growth, Business or Pro plans, and migrations from other ATSs are available to Pro customers.

Breezy says migration review takes about 2 business days and migration is typically completed within 7 business days once data and subscription details are in order. Admins should validate imported data and report issues within 3 days, so plan time for checking.

Ashby is the stronger example for scaling teams that want ATS, CRM and analytics in one platform. ATSLab records Ashby at $400 and ranks it second, but its richer data model means the migration design matters more.

Ashby's All-in-One Foundations plan is listed at $400/month for companies up to 100 employees, with a 10% discount available for annual commitments. Plus and Enterprise are positioned for larger companies, but public dollar pricing is not listed for those plans.

Ashby supports API migration, file-based migration and self-serve bulk import. API migration completes automatically in 2–3 days depending on data volume, but support is for Greenhouse and Workday, plus some Lever migrations.

Ashby's self-serve bulk import supports CSV candidate data and resume folders. The limitation is important: Ashby says this generally is not a comprehensive view of a candidate's lifecycle with a team.

Greenhouse is the enterprise structured-hiring benchmark if you need mature scorecards, interview kits and complex governance. ATSLab records Greenhouse at From ~$6k and ranks it nineteenth, while Greenhouse itself does not publish fixed dollar pricing publicly.

Greenhouse's public plan names are Core, Plus and Pro. Core includes sourcing and CRM, structured interview kits and scorecards, AI Notetaker, scheduling, reporting, SSO and Real Talent Talent Matching.

Greenhouse Plus adds AI-powered report filters, Business Intelligence Connector, Sourcing Automation, Texting and Real Talent fraud and spam detection. Pro adds enterprise data configuration, security, audit log, developer sandbox and sync.

Greenhouse says teams can keep recruiting with active candidates while it completes historical data migration from the former ATS, which takes 4–6 weeks. That is useful for large teams, but it requires contract overlap and a clear active-candidate plan.

For bulk import, Greenhouse recommends no more than 8,000 candidates at a time and supports a resume .zip up to 5 GB. Its support pages describe bulk import tier availability differently, so buyers should verify access during sales and onboarding.

How much does an ATS migration cost?

Budget for more than the new subscription. The real migration cost includes implementation, vendor-assisted migration, third-party help, API access, contract overlap, integrations, training and admin time.

For Breezy HR, include the $157/month recorded entry price, then check whether you need annual Growth, Business or Pro for migration eligibility. Also budget for Breezy Intelligence credits from $30 per 100,000 credits, SMS credits from $41/month, Onboard from $49/month and possible migration fees above 25,000 records.

For Ashby, start with the $400/month Foundations figure if you are up to 100 employees. Then ask about Plus or Enterprise pricing, SMS overage at $90 per 1,000 messages, AI credit needs and any paid add-ons that affect rollout.

Ashby includes 200 sourcing email lookups across Foundations, Plus and Enterprise, with more available as a paid add-on. That is helpful for sourcing teams, but it can become a budget line if migration coincides with a hiring push.

For Greenhouse, ask for a line-item quote. The quote should cover plan, implementation, migration or import assistance, onboarding, texting, Real Talent, BI Connector, sandbox or developer tools and integrations.

Contract overlap is easy to underestimate. If Greenhouse historical migration takes 4–6 weeks, or if your team needs two payroll cycles to validate HRIS handoff, cancelling the old ATS too early creates avoidable risk.

What should you ask ATS vendors before signing?

Ask exactly what data objects migrate and which are excluded. A vendor saying it can import candidates is useful, but it does not answer whether scorecards, notes, attachments and offers survive.

Ask whether resumes, signed offers, rejection reasons, source tags, EEO data and consent fields are preserved. If they are not, ask whether they can be archived, attached as files or exported for compliance use.

Ask whether migration is included in the plan. If it is not, confirm the fee, record limit, rework policy, validation period and whether failed imports are corrected without extra cost.

Ask whether the old ATS must provide API access. Some moves are simple exports, but richer migrations may depend on API permissions, admin access and vendor cooperation from the system you are leaving.

Ask how active candidates are handled during migration. You want a clear answer covering freeze timing, final delta import, interview schedules, feedback, offers and candidate communications.

Ask whether you can run a test import before final cutover. If the vendor refuses, the risk shifts to your team, because field mapping and duplicates will be discovered after recruiters are live.

Ask what data you can export if you leave the new ATS later. A clean exit path is rarely exciting during purchase, but it matters the next time your hiring process changes.

Final cutover checklist and recommended next steps

Cut over only when active candidates are accurate in the new ATS. Check job, stage, owner, next step, scheduled interviews, pending feedback and offer status before routing new applicants there.

Confirm careers pages and job postings point to the new system. Then test calendar, email, HRIS, background checks, job boards, assessments, e-signature, Slack, analytics and SSO where used.

Confirm permissions before hiring managers log in. Recruiters may have full access, but interviewers and executives often see broken workflows first because their roles are narrower.

Run report checks against expected counts for jobs, candidates, applications, hires, rejections, sources and funnel stages. A mismatch does not always mean the import failed, but it must be explained before old data is archived.

Breezy HR is the best fit in this migration scenario if you are a startup or small business moving from a supported ATS and want a clear, lower-friction path. The limitation is that migration eligibility depends on annual Growth, Business or Pro plans and supported source systems.

Ashby is the better fit if you are scaling hiring volume and need ATS, CRM and analytics in one data-rich system. The trade-off is that richer setup and plan choices need more careful migration design.

Greenhouse is the enterprise option if structured hiring, scorecards, governance and complex workflows matter most. Buyers should validate custom pricing, migration support and bulk import access before signing.

Keep old-system access until validation, retention, legal hold and export requirements are complete. Import success is not the same as migration completion.