Switching HR software: the export test, the parallel month and the cut-over checklist
Staying with the wrong system because moving feels risky is how companies end up paying for software everyone works around. The move itself is a six-week project with three known hazards - all avoidable if you plan for them.
Export everything early, run old and new side by side for one payroll cycle, and cut over at a quiet point in your leave year with a written list. The three hazards: data you cannot get out of the old system, balances that disagree between systems, and compliance dates that fall between the two. Each has a section below.
Should you switch at all?
Switching costs a month of someone's attention, so switch for structural reasons: a pricing model that has turned against you (per-module fees stacking up, a tier jump forced by one feature), data you cannot get out or reports you cannot build, or a system your managers quietly route around with spreadsheets - the surest sign of all, because you are paying for software and doing the work by hand. Do not switch because a demo looked shinier; demos always do. If you are re-choosing, do it properly - our buyer's guide and requirements checklist are the method, and this time weight the exit questions, because you now know what being stuck feels like.
Getting your data out: the export test
Do the export first, not last - it is both your migration source and your leverage. Ask the incumbent for a full export and look at what actually arrives: people and contract data, leave history and balances, sickness records, documents (contracts, right-to-work evidence), and anything sector-critical like training or DBS records. Three things to watch: documents are the most commonly incomplete part of an export - check a sample person's file end to end; formats matter less than completeness, since a messy CSV can be cleaned but a missing field cannot; and timing - export while your subscription is healthy, because an exit-week export request tests the vendor's goodwill at exactly the wrong moment. You learn a lot about a vendor at export time; it is the moment their incentives stop pointing at you.
The parallel-run month
Load the new system, then run both for one full payroll cycle. Approvals happen in the old system (it is still the system of record); the same events are mirrored into the new one, and at month end you reconcile: headcount matches, leave balances match person by person, the payroll export from the new system agrees with what the old one produced. Every discrepancy found in the parallel month is a data-cleaning task; the same discrepancy found after cut-over is a payroll error with a person attached. This is also the month to let managers try the new system with real requests - training against live data beats any walkthrough.
The cut-over checklist
- Leave balances as at the switch date - agreed, person by person, including carry-over and TOIL. This is the number employees will check first.
- Open items - pending leave requests, in-flight expenses, unfinished onboarding: close them in the old system or re-raise them in the new one, but decide item by item, in writing.
- Compliance dates - right-to-work expiries, probation ends, training renewals, DBS renewals if you track them: confirm each register is complete in the new system before the old reminders switch off. A date that falls between systems does not chase itself.
- Documents - spot-check migrated files against your export archive; verify the sensitive ones (contracts, RTW evidence) opened correctly rather than trusting the file count.
- Payroll and integrations - point the payroll export at the new system and tell your accountant or bureau the format is changing before they discover it.
- Access - everyone can log in before day one, managers know where approvals now live, and the old system goes read-only (not deleted) on the switch date.
Telling the team
One honest note beats a campaign: what is changing, the date, the one thing everyone must do (log in, check your balance, tell HR if it looks wrong), and why the company is moving - people co-operate with a reason more than an announcement. Asking everyone to verify their own balance in week one is not an admission of doubt; it is a hundred free auditors, and the questions it surfaces are the migration bugs you want found in week one rather than at Christmas.
The first 90 days: actually leave
Keep the old system read-only until you have survived one quarter and one leave-year event (a carry-over, a bank-holiday calculation), then export a final archive, store it access-controlled - retention obligations on records like right-to-work evidence outlive the software they were recorded in - and cancel. The failure mode is running both systems forever "just in case": you pay twice and nobody trusts either. And hold the new vendor to the standard that made you switch: if the move has not made the Monday-morning admin visibly lighter within a quarter, say so to them - a vendor worth staying with will want to know.
Frequently asked questions
How long does switching HR software take?
For a company of 20 to 150 people, plan six to eight weeks end to end: a week or two to export and clean your data, a couple of weeks to load and check it in the new system, one full payroll cycle running both systems in parallel, and a clean cut-over. The parallel month is the part people skip and regret.
When in the year should we switch?
At a quiet point in your leave year, after payroll has run and before a request surge - for many UK companies that means early autumn or the start of the leave year itself, and never the weeks before Christmas requests land. Switching at leave-year start makes balance carry-over arithmetic much simpler.
Will the new vendor migrate our data for us?
Ask - practice varies from CSV imports you run yourself to a managed migration, sometimes at extra cost. Whoever does the loading, the checking is yours: reconcile headcount, leave balances and key dates against the old system before anyone relies on the new one.
Do we lose our history when we switch?
You should not - export everything from the old system before your access ends and keep the archive somewhere access-controlled, because right-to-work evidence and disciplinary records have retention obligations that outlive the software they were recorded in. What you load into the new system can be slimmer: current records, balances and open items, with the archive held for reference.
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Switching to CoDash
CSV imports for people, balances and history, a demo you can rehearse the whole move in first, and our own exit terms in writing - export at any time, including after you stop paying. We built the door out because we ask every vendor for one.