The ultimate HR system switch survival guide

If you’re reading this, you’re probably running HR on a stack built out of “just get it done” decisions. It mostly works—until it doesn’t. The problem usually isn’t one bad tool. It’s the handoffs: the file feeds that break, the duplicated fields, the 8 p.m. “who owns this?” scramble before payroll. It’s not just messy—it’s risky.

But what if the risky move isn’t switching—it’s staying? Every month you hang onto that patchwork of disconnected tools, you pay for it: duplicate records, manual fixes, compliance risk, errors, and credibility with finance when payroll and the GL refuse to line up.

You don’t need a pep talk. You need a plan. This eight-week guide gives you one: a clear, realistic project plan to switch HR systems by Jan. 1 so your next year runs on just one platform.

Paige Erickson led Forbes Advisor through a global switch off five platforms, going live on Rippling with just an eight-week runway.

“Once we had buy-in and 100% sign-off, to move forward with Rippling, it was just under 10 weeks—maybe even eight—to get everything up and running for Jan. 1,” she said.

The switch was worth it to help Forbes Advisor go from processing five different payrolls on five different platforms every month to just one. And you can, too. If you want to start 2026 with one seamless, integrated HR system, this is your survival guide—and your step-by-step plan—to switch with confidence and start 2026 fresh.

Why now (and why is your window closing)?

The sweet spot to select, implement, test, and cut over to a new HR and payroll system is spring through early fall. Right now—August—is still prime time.

You can technically switch any time of the year, but year-end cutovers are cleaner and less complex because it means starting the new year running payroll in one system. If payroll is split between two systems in January, employees’ W-2s and year-to-date tax records get fragmented across multiple providers, leading to tax complications and compliance risks.

But don’t wait until too close to the start of the new year. Here’s why a late Q4 cutover can put your team in a bind:

• Open Enrollment collides with implementation.

  If you start late, your team will have to configure a new system while managing plan changes and employee elections. The overlap multiplies risk and drains capacity when you need accuracy most.

• Testing time gets squeezed.

  Best practice when switching systems is to run test scenarios and/or parallel payrolls before you cut over, then reconcile taxes, deductions, garnishments, and accruals to make sure the new system is running everything accurately. In late Q4, holidays and PTO make testing harder to schedule—and if you uncover any issues, remediation can be more complex, too.

• Year-end payroll and tax work leave no margin.

  Closing out the tax year is deadline-driven. If your new system isn’t stable, you risk missing important deadlines or making errors that could cost your business in compliance penalties or take significant time and effort to solve.

If your goal is to run 2026 payroll on one system, an eight-week sprint gives you just enough time to get it done. But Paige notes another consideration to keep in mind: “Make sure you can get out of your contracts and you’re providing that notice as soon as possible.”

Eight weeks is long enough to choose the right vendor, clean your people data, train managers, and run at least one full parallel payroll cycle (preferably two) so you can find and fix problems before Jan. 1. But the latest you can start an eight-week implementation plan is late October—and ideally, you’d start preparing now. The first steps are to set your goals, align with stakeholders, and get buy-in and commitment from executives, which is why you need to start by building a case for why you need to switch systems (and why now is the right time).

Make the case: Translate the switch into C-suite value

You don’t win approval for a change like this by listing features. You get there by framing the change in outcomes each leader cares about (and already owns).

Want a shortcut for tailoring your pitch? Download the HR platform buyer’s guide to see how to build a messaging matrix—a simple tool that maps your case to each stakeholder’s perspective, priorities, and success metrics. It includes a sample matrix you can adapt for your CEO, CFO, CTO, and other leaders so every conversation hits what matters most to them.

Here’s how to pitch your HR system switch to the C-suite by tying your business case to business value:

You got buy-in. Now what?

You have the green light. Now your job is to turn “we’re switching” into a steady, repeatable plan that leaders can trust and your team can run.

For Paige’s team, the idea was to use the eight-week window to land “the big stuff”—payroll, benefits, and imports—by Jan. 1. Less crucial, “nice-to-have” modules (like performance management) can be added later, once the initial sprint is done.

“It wasn’t a full eight weeks [for] everything,” Paige said. “We got the big stuff done.”

So below, you’ll find an eight-week plan that reflects what worked in practice for Paige’s team: Lock contracts, land payroll and benefits first, stagger the rest, and over-communicate throughout the switch.

Critical dependencies

These are the items that quietly make or break your cutover. Treat each one like a mini project with an owner, a due date, and proof of completion.

Accurate YTD data

Import and verify year-to-date wages and taxes (federal, state, and local), taxable vs. non-taxable benefits, pre- and post-taxable deductions (401(k), HSA/FSA, transit, etc.), garnishments, accrued PTO balances, leave statuses, and current benefit elections. Include any former employees paid this year.

Make sure to get a detailed register from your old payroll system through the final December payroll. Map legacy pay codes to the new system’s pay codes and run a tie-out comparing employee-level and company level totals line-by-line for accuracy.

Benefits carrier sync

Confirm benefits eligibility files (including medical, dental, vision, life/AD&D, disability, FSA/HSA, and COBRA eligibility) so January deductions and coverage align on day one. Make sure effective dates, plan options, and employee tiers match your plan documents.

Tax registrations

Transfer or verify state and local tax registrations into the new system for every work and withholding location. You’ll need to include federal EFTPS setup, state unemployment (SUI) and withholding (SIT) accounts, and local tax jurisdictions (for city, county, and school district levies). Verify account numbers and deposit frequencies for every location where employees work or reside, and confirm quarter-end and year-end filing responsibilities with the vendor in writing.

Direct deposit

Reverify bank accounts in the new system using microdeposits or an equivalent check, so there are no day one payment delays. It’s also best practice to set a cutoff date for employees to update their banking details, and be ready to issue paper checks to employees whose verification fails.

Risk mitigation

Put guardrails in place to keep the switch plan steady as the calendar tightens. These risk mitigation strategies should be an explicit part of your plan—they’ll keep you on deadline when things go wrong.

Parallel run

It’s best practice to process at least one full payroll cycle in both systems and reconcile net pay, taxes, deductions, employer costs, garnishments, and accruals down to the penny to look for gaps or errors. It’s better if you can do two parallel runs.

How to do it: Pick a pay period (ideally four weeks out from your go-live date) to run both payrolls concurrently. Export comparison reports, find any variances, and immediately assign them to owners to fix. If variances persist, document the root cause, fix configurations or data, and re-run a spot check before cutover.

Cutover freeze

Two weeks before go-live, put a freeze on major organizational changes: No new states, entities, acquisitions, restructures, comp plan overhauls, or policy rewrites.

How to do it: Publish a one-line policy: “Changes requiring policy, tax, or structural updates are deferred until after Jan. 1 go-live.” If any major change absolutely must occur during that window, require steerco approval and explicit re-testing before cutover.

Communication plan

Transparent communication with employees and managers about (and throughout) the switch will build trust and reduce tickets.

How to do it:

• Provide managers with scripts and FAQs covering approvals, where to log in, and how to help their teams

• Make a general announcement to employees covering any changes to their paystub formats, where and how to update their personal information, and how to get help

Start here to build your RFP

Download the Must-have HCM RFP template and use it to set scope, align timelines, and compare platforms on their ability to meet your business needs, dependencies, guardrails, and more.

Make the switch without the stress

“It's a very nerve wracking jump. I get that, especially because the burden does land on the individual in HR who's making this move and making this decision,” Paige said. “But I can tell you it changed the game for us on a daily, on a monthly basis—our workflow, our processes. And if there's anything that you are feeling like you're not getting through your current HRIS system, it's definitely worth the switch.”

You don’t need heroics to start the year on one system—you just need a calendar, clear owners, discipline to keep the scope tight, and, most importantly, a plan. While Jan. 1 is the cleanest time to switch, you can still invest in a better HR system even if you’ve missed that deadline. Here’s what to do next:

1. Pick your first payroll on the new system and back-plan. Choose the pay period you want to run, name owners in HR/Payroll/Finance/IT, and align on the 10-week schedule you’ll follow.

2. Send your RFP and set a decision date. Use our Must-have HCM RFP template to capture your scope and timeline, book demos, and find the right platform for your business needs.

If an all-in-one platform is on your radar, we can show you how fast and easy it is to make the switch to Rippling, using your timeline, your policies, and your plan. Request a demo—live or on demand—to see how Rippling can help you manage all of your employee data and operations in one place, no matter your business’s size.