There is no straightforward answer to this question as it depends on the size and complexity of your organisation, what systems and processes are already in place and what resources are available.
However, in URM’s experience it typically takes between 6 and 9 months for a small, low complexity organisation to fully implement ISO 27001.
With larger, more complex environments, 9 to 18 months is closer to the norm for fully establishing an ISMS. This naturally assumes that the appropriate resources are made available to achieve the desired outcomes.

Internal Auditing of Management Systems
URM’s blog explains how to plan and execute effective and conformant internal audits of management systems at each stage of the internal audit process.
URM’s blog explains how to conduct information security risk assessments and implement risk treatments that are both efficient and ISO 27001 conformant.
URM’s blog explains what ISO 27002 is, how it can benefit your organisation, & how you can use it to support your implementation of an ISO 27001-conformant ISMS
URM’s blog explains why ‘people’ warrants its own control theme in ISO 27001 and how to prepare for a people controls audit, offering advice for each control.

