Building a Realistic Migration Timeline Before It's Too Late

Building a Realistic Migration Timeline Before It's Too Late

Work backward from December 2027, account for how long these projects actually take, and the amount of runway left starts to look a lot shorter than it feels.

Most of the research covered in this series eventually points to the same practical question: given how long these projects actually take, how much time is genuinely left? The honest answer depends heavily on your organization's complexity, but the industry's own estimates leave less margin than most planning conversations assume.

Duration estimates from independent research cluster in a wide but informative range. Gartner has told clients to expect migration projects lasting anywhere from three to seven years for the most complex, heavily customized global landscapes, particularly where a genuine process redesign and change-management effort are involved rather than a like-for-like technical conversion. More typical estimates for a standard enterprise migration put the range at 12 to 24 months, while complex, multi-country programs with significant custom code tend to run 30 to 42 months from kickoff to stabilized go-live. ASUG's member survey, drawing on real completed projects, found an average duration of roughly one and a half years — useful as a planning anchor, though it likely understates the true range given how many respondents are past the most complex end of the distribution.