To be entitled to the state pension an individual usually needs to have made 35 qualifying years of NI contributions.
It is possible to make voluntary contributions to fill gaps back to April 2006, but this will be restricted from April of this year.
The ICAEW have produced a checklist of actions for anyone who might be affected by this issue.
Related content from Claritax Books
The complex rules for National Insurance contributions are covered in depth in National Insurance Contributions, by Karen Speight.