Moving 500+ employees from ADP to Definitiv

Published 7 October 2026 · Team member career experience

These stories describe experience gained by a SESAY team member in previous employment roles. They are not presented as SESAY client engagements. Employer and employee names are omitted. Outcomes reflect the team member’s career records and are not guarantees of future results.

3 entities · 500+ employees

Situation

Three large, multi-award employing entities were transitioning from ADP to Definitiv. The migration covered more than 500 employees within a complex payroll environment, where different employment arrangements and operational requirements had to be reflected in the new system.

Task

A SESAY team member led the transition. The responsibility was broader than moving employee records: payroll configuration, data integration, testing and operational readiness all formed part of the work.

Action

The team member led configuration, integration, testing and validation for the transition. Their wider implementation experience included analysing payroll rules where documentation and knowledge transfer were limited, and strengthening change control around system configuration. The work connected the technical setup with the operational requirement to continue paying employees through the change.

Result

The career record reports successful ADP-to-Definitiv transitions with no disruption to employee payments. The documented scope includes the three-entity, 500-plus-employee transition. No claim is made that a successful migration removes the need for ongoing review or guarantees the same outcome for every implementation.

What this experience brings to SESAY

SESAY brings this experience to system transitions by focusing on configuration, data quality, testing and operational handover together. A platform change is a payroll delivery project as well as a technology project.