Why Most Cloud Migrations Go Over Budget

Across the cloud migration projects we've reviewed, actual cost has averaged 30% higher than the initial estimate. The reason usually isn't complicated.

Reason 1: Estimates based on list price, not actual usage patterns

Cloud pricing is based on actual consumption, not a fixed monthly number. Without analyzing current traffic and storage patterns, any estimate is a guess.

Reason 2: Forgetting data transfer costs

Data egress costs from cloud services are often missing from initial estimates, yet can be a significant share of the monthly bill.

Reason 3: A "big bang" migration instead of a phased one

Migrating every service at once raises the chance of errors and the resulting cost to fix them. A phased migration allows course correction before full commitment.

Reason 4: No post-migration review

Resources over-provisioned during migration for extra safety margin, if never reviewed later, stay oversized and overpriced indefinitely.

Bottom line

The fix is a precise Cloud Assessment & Roadmap before you start, not hoping the initial estimate holds.