If you are planning an HR technology implementation, you probably have the software choice and the build covered. The part that catches many teams out comes later. An implementation has five stages, and the first four usually have an obvious owner: selection, build and configuration, data migration and go-live. The fifth, running the system once the project team has gone, often has no name against it. Here is what each stage needs, who is best placed to do it, and where the gap opens.
An HRIS implementation is the project that takes a human capital management platform from purchase to live payroll. Administration is a separate job that begins the day the project ends. If you are still choosing between platforms, start with choosing the right HCM platform instead.
Corban OneSource runs HR technology for its clients, so the final stage describes work we do. Outsail is named because they advise on selection and we do not.
Key Takeaways
- An HR technology implementation has five distinct stages, and each needs different people; one vendor rarely covers them all.
- Selection is the one stage where a vendor-neutral advisor answers a question the platform vendors structurally cannot.
- Data migration is where timelines slip, because the quality of historical data only shows up once you start moving it.
- The stage most often left unstaffed is the fifth, after go-live, when the project team disbands and the system becomes somebody’s day job.
The Short Version
The five stages, in order:
- Selection. Decide what you are buying and why.
- Build and configuration. Shape the platform to your pay rules and org structure.
- Data migration. Move history across and reconcile it.
- Go-live and parallel running. Run both systems and compare outputs until they match.
- Running it afterwards. Operate the system as a permanent function.
Stages 1 through 4 have an obvious owner on almost every project. Stage 5 is the one to name before you start.
| Stage | What it produces | Who is best placed | Common failure |
|---|---|---|---|
| Selection | A decision you can defend | A vendor-neutral advisor | Chosen on demo quality alone |
| Build and configuration | A platform shaped to your rules | The platform vendor's implementation team | Modules bought and never configured |
| Data migration | Clean, reconciled history | Your team plus the vendor, jointly | Under-resourced relative to configuration |
| Go-live and parallel | Verified output | A named internal owner | Treated as a formality |
| Running it afterwards | A system that stays current | In-house, consultant or managed partner | Nobody is named before the project closes |
Assumptions: a single-country US implementation for a midsize employer replacing or introducing one HCM platform. Timelines and costs vary with module count and data quality, and are discussed qualitatively below.
Stage 1: Selection
Selection is the only stage where a vendor-neutral advisor can answer a question the platform vendors structurally cannot.
Every vendor in a competitive process is a credible source on their own product and an unreliable one on the comparison. That is simply the position they occupy. An advisor who does not sell a platform can run the comparison on your own requirements, where vendors tend to lead on feature breadth.
Outsail works this stage. Outsail describes itself as a vendor-neutral broker that does not sell implementation services: buyers get its selection platform, vendor profiles, scorecards and proposal analysis, and its core services are free to buyers because vendors pay Outsail a commission on a purchase. It also sells paid tiers, including support during implementation. Its own guide to the category, published August 2026, ranks firms by how well each fits a specific buyer’s needs.
The common mistake here is choosing on the quality of the demo. Write the requirements list before the demos start, and choose against it.
Stage 2: Build and Configuration
Configuration is where the platform is shaped to your pay rules, and it is usually delivered by the platform vendor’s own implementation team.
This is the stage with the clearest ownership, because it is normally included in what you bought. Pay groups, earnings and deductions, org structure, approval chains, benefits plans and the first set of reports all get built here, against a statement of work with a defined end date.
Scope is where this stage slips. Modules that were licensed and left unprioritized get deferred to a phase two that never gets scheduled, and the employer discovers a year later that they are paying for capability they never configured.
Stage 3: Data Migration
Data migration is the stage that slips, because the quality of historical data only shows up once you start moving it.
Nobody knows how clean their data is until they try to move it. Year-to-date wage and tax figures have to reconcile exactly, because they feed year-end filings. Benefits elections, accrual balances, employment history and manager hierarchies all need mapping, and every inconsistency that has been tolerated in the old system becomes a decision in the new one.
Teams often size the effort by the number of records when it is the data quality that drives it, and migration ends up under-resourced compared with configuration.
Stage 4: Go-Live and Parallel Running
Parallel running is a verification period, and it needs someone whose actual job is to compare the two outputs.
For at least one full cycle, and usually more, both systems run and the results are checked against each other line by line. Discrepancies are found, traced to a configuration decision, and fixed. The value of the stage is entirely in the comparison, which means it collapses if the comparison is nobody’s assigned work.
The risk is treating the parallel period as a sign-off, so the first real error surfaces in the first unsupported payroll.
Stage 5: Running It Afterwards
The project ends while the system keeps running, which is where the gap opens.
On the Monday after cutover the implementation team stands down and the platform becomes an operating responsibility: processing, employee questions, configuration changes when a plan or pay rule moves, reporting, and the annual rebuild for open enrollment. None of that was in the statement of work, and in many midsize organizations none of it has a name against it either.
This is the stage Corban OneSource takes on, as a permanent function, through our fully managed HR technology services.
Whoever takes this stage on, name them before the project team stands down, because the platform’s first month live is when unowned work piles up fastest.
Which Stages Can You Cover Internally?
Many midsize teams can cover two of the five well, and should be honest about which two.
The two usually within reach are data migration, because your team knows the history better than anyone external, and the internal half of parallel running, because your people know what the output should look like. Selection and configuration are specialist work done rarely, which is why buying them in is normal.
Stage 5 is the one to decide deliberately, because it is permanent, and what running a platform after go-live involves is worth reading before you do.
What Does an HR Technology Implementation Actually Cost You in Time?
Most of the internal time cost falls in migration and parallel running.
Selection feels expensive because it involves meetings, but the hours are modest and they are spread over weeks. Migration and parallel running are where your own people lose days, because the work cannot be delegated outward: only your team can say whether a reconciled figure is right.
Plan for Life After Go-Live with Corban OneSource
The implementation team will leave, and the platform will still need running. At Corban OneSource, we take on that fifth stage as a permanent function: a named team runs the platform day to day, and employee questions go to our HEROES support team.
There is no co-employment, so you keep your own FEIN, control over your company culture and your own benefits packages. Our pricing is predictable, per employee per month, and does not penalize you for growing your payroll. Corban reports savings of up to 32% against running these functions with an internal team, on its own site. We act as a seamless extension of your internal team. Schedule a consultation to plan who runs your platform after go-live.
FAQ
Long enough that you should plan it around your fiscal and benefits calendar. The variables that move it most are the number of modules, how clean your historical data turns out to be, and how quickly internal decisions get made during configuration. Treat any fixed duration quoted before someone has seen your data as a sales timeline.
Often not for configuration, since that is what the vendor’s team does and they know their own product best. The case for independent help is strongest at selection, before you have chosen, and at stage five, after the vendor’s team has gone. Those are the two points where the vendor cannot help you by definition.
In practice the terms are used interchangeably and the project is the same shape. HRIS historically meant core records and payroll, while HCM implies a broader suite including talent and performance. The label matters far less than the module list in your statement of work, which is the thing that actually determines effort.
One named person with authority to make configuration decisions without convening a committee. The most common failure is a project sponsored by HR, affecting finance and IT, with no single person able to settle a disagreement between them. Seniority matters less than decision rights.
Small configuration gaps that parallel running did not surface, employee questions nobody is assigned to answer, and reports that existed in the old system and were never rebuilt. None of these is serious individually. Together they decide whether people trust the new system, and trust is difficult to recover once lost.
It is strongly inadvisable. Open enrollment is the heaviest configuration and highest-visibility period in the HR calendar, and overlapping it with a cutover means your least familiar system is handling your least forgiving process. Finish before enrollment opens, or start after it closes.
Related Reading - HCM Comparisons
- Paycom vs. ADP Workforce Now: Which HCM Software is Right for Your Business?
- Workday vs. ADP Workforce Now: Choosing the Right HCM Platform for Your Growth Strategy
- Paylocity vs. Workday: Choosing the Right HRIS for Your Business
- Dayforce vs. ADP Workforce Now: Why Growing Companies Are Making the Switch to ADP
- Paylocity vs. Paychex: Why Growing Companies Are Upgrading Their HCM Systems
Disclaimer
This article describes the stages of an HR technology implementation and who typically handles each one. It is not legal, tax or employment advice.
Connect with us to learn more about HR Outsourcing!
