HR data migration: A step-by-step guide for UK businesses

HR data migration is the process of transferring your data (including employee records, documents, payroll and performance history) from one place to another. It also covers all the steps before and after migration—like preparing and cleansing data, mapping fields and validating that everything has transferred successfully.

Common reasons to move employee data include when you switch from spreadsheets or legacy HR software to a dedicated HR platform, moving from one HRIS (HR Information System) to another, or when you consolidate several tools into an all-in-one HR system.

The type of data that you migrate depends on the type of move you’re making. If you’re switching to a new HR system, you’ll need to move personal records, absence records, documents and more. If you’re moving from one payroll tool to another, the list of what to prepare is smaller and more specific.

Here are the main types of employee data that HR teams migrate:

As well as the reasons to keep or migrate the data given above, you’ll also need to consider whether there are any legal requirements on which information to keep and for how long. Our compliance section below goes into more detail on this.

Successful data migrations involve more than downloading records from one system and uploading them to the new one. Here’s how to manage data migration for a new HR system.

Create a comprehensive map of all your existing data so you don’t miss anything. Start by identifying what data you hold, where it lives and whether it’s high-quality or not. This includes not just your current HR software but also spreadsheets, documents and other standalone HR tools.

Once you’ve mapped out your data, decide what to do with it. Review the information you hold and decide whether it should be transferred, archived or discarded (or deleted). For any data you plan to migrate, note down whether it’s ready to transfer or requires extra preparation.

Complete a data cleansing step before you import data into your new HR platform. Remove duplicates, correct errors, and standardise formats—especially for fields that relate to dates and pay. This is where most migrations run into problems, so take extra care to make sure your data is consistent.

Match the fields from your legacy system or spreadsheets to the fields in your new HR platform. This step is essential as it means your data will appear as expected in the new system. Most HR software providers will be able to provide you with a template spreadsheet or information about required and optional fields to make this step easier.

Decide which migration process is best for you and put plans in place to make it happen. Choose from a phased or full cutover process (where you migrate everything at once) and whether you want to DIY your migration or get help from a dedicated implementation support team. 

Many HR managers ask “can we migrate our data from our old system?” and the answer in most cases is yes. Most HR software providers allow you to import your own data, but many also offer a guided or supported implementation process. 

Create a complete record of your employee data and records before you begin the migration process. This ensures you have a master copy of all the data you hold, and you’ll be able to handle any situations where data doesn’t transfer as expected. 

Complete the HR data migration process. Often this will involve support from your HR software provider, who will handle the technical side of the process along with any training requirements or questions you might have.

Check that all data has been transferred correctly. Make sure nothing is missing, no data has become corrupted and that everything is as expected—including year-to-date figures for absences and payroll, holiday balances and any document attachments or files.

Once you’re happy that the migration process was successful, update employees on the move. Set permissions, update integrations and configure your settings so they’re ready to go. Send invites to employees and invite them to training sessions that prepare them on how to use the system. 

When you’re satisfied that everything is working correctly, you can decommission your old HR system or series of tools. Do this only after you’ve completed an internal audit to make sure you no longer need any data or workflows that exist in the old platform.

There are risks involved with transferring large amounts of data from one tool to another, but the right planning and preparation can help you avoid these potential pitfalls.

While you may not have full control over the technical side of data migration, being aware of the risks above and how to deal with them can help you prepare for any worst-case scenarios and talk them through with your implementation team.

UK-based HR managers need to be mindful of their responsibilities when it comes to employment legislation, data protection legislation and the UK GDPR.

Here are the key compliance considerations when migrating HR data:

• HR data is personal data and migrating it counts as a data processing activity.

• Document the lawful basis for data processing in the new system before migration.

• Make sure your new HR system stores data in accordance with data protection regulations and the UK GDPR.

• Do not migrate data that is no longer needed or past its retention period.

• Review your privacy notices to confirm whether you need to seek fresh consent for data processing or not, but typically you won’t need to.

Note: HR teams should consult their Data Protection Officer or legal counsel on matters that relate to UK GDPR compliance.

Some HR platforms make it easier to import and organise your data than others. While some vendors have a lengthy and complicated implementation process, others allow you more flexibility and control over your data and what happens with it.

Here’s what to look for if you want a more seamless experience when migrating your people data:

• Easy bulk data upload: Can you upload your own people data, and can you do it in bulk from a spreadsheet?

• Field-mapping guidance: Does the vendor offer guidance on how to map fields correctly? Is there a spreadsheet template you can use?

• Structured implementation support: Is there support available for the data migration and implementation process?

• Support for UK GDPR compliance: Does the vendor have the right structure in place to support compliance with UK GDPR and other relevant legislation?

• Futureproofing against further migrations: Is this an all-in-one system that reduces the need for future software moves? 

Data migration can be a time-consuming process, but it shouldn’t feel difficult. Don’t be afraid to ask your potential vendors some tough questions so you can understand whether it’s the right experience for you or not.

Migrating to Personio looks a lot like the process we outlined above, but with the added benefit of our dedicated implementation team and data migration support service. Whether you’re migrating HR data from Employment Hero, Rippling, HiBob or another HR platform, we can help.

We’ll migrate all the necessary information like employee records, absence history and documents—including historical data. We know that losing historical data is a major concern for HR teams, but with our team’s expert support this won’t be a concern. 

The data migration process looks different depending on the software you choose, but some things are essential: like mapping data, preparing internal comms and asking for the final go-live date.

Use this HR data migration checklist to make sure you don’t miss an important step: 

• Set your data migration goal

• Complete a full data export from your existing HRIS

• Gather all your relevant HR data in one document or drive

• Create a field mapping document and map your data 

• Check that every record is complete, with no inaccurate or missing information

• Ask your chosen vendor for an implementation timeline

• Create a HRIS implementation plan

• Continue to use the existing HRIS for existing HR and payroll needs

• Check for any recent legislation or in-house policy changes that require you to make adjustments to the workflows, settings or timeline

• Ask your implementation team for regular updates on progress

• Confirm the final go-live date with your vendor

• Schedule a call to discuss any post-implementation issues or questions

• Prepare guidance for employees on how to use the new system

• Create a simple internal comms plan that promotes engagement

• Confirm that all employee absence balances are accurate

• Check that payroll year-to-date figures are correct

• Thoroughly test the new HRIS

• Schedule training sessions for team members (if required)

• Update integrations and make sure data flows correctly

• Revoke access to your legacy system for all users

• Close your account with your previous HRIS provider

• Regularly monitor the performance of your new HR system

Switching HR platforms is one of the most data-sensitive decisions an HR team makes. Personio is built to make that transition as smooth as possible, with structured implementation support, clear field-mapping guidance and a dedicated data migration support service that works with your team from the start.

When you migrate to Personio, employee records, absence history, payroll year-to-date figures  and documents all move into a single, centralised platform. That means no more reconciling data across disconnected tools, and no more risk of historical records getting lost in the switch.

Personio stores data in line with UK and European data protection standards, so the compliance considerations that matter to your organisation are built into the platform from day one. And because all HR data lives in one place after migration, the risk of needing to go through this process again is significantly reduced.

Whether you're moving from spreadsheets, a legacy system, or a platform like Employment Hero or BambooHR, Personio's implementation team supports you through every stage, from data audit to go-live.

Book a demo to see how Personio handles HR data migration.

Most modern HR platforms support data import, but the level of support varies. Legacy or highly customised systems may require a more advanced and manual process. Check with your new vendor’s implementation team as soon as possible so they can help you plan the best way to migrate your data smoothly.

Migration timelines vary from several weeks to several months, depending on the volume of data, the amount of legacy information and how much data cleansing is required. The average Personio implementation time is six weeks, but it will depend on what's in your HRIS implementation plan.

Data should stay live in the old HR system until you’re confident that everything has migrated correctly. Once you’ve validated that everything works properly, remove employee access to the old software and take steps to close the account and remove data in line with your organisation’s data retention policy.

Yes, if it’s handled correctly. HR data counts as personal data under the UK GDPR, so organisations must ensure data is transferred securely, that only necessary data is migrated and that the new system processes data on a valid lawful basis.

Most modern HR platforms support data import via a CSV (comma separated values) file or structured file upload. The process varies by vendor, but it should be relatively straightforward once you’ve mapped out your data.