How often should I refresh or migrate digital archives to prevent data loss?

There is no single calendar interval that fits every digital archive. Instead of asking “how often,” it helps to think about two distinct activities and the conditions that should trigger each one.

Refresh vs. migrate

These terms are often confused but address different risks.

• Refresh (media renewal): Copying the same bitstream onto fresh storage to guard against physical media decay and hardware failure. Storage media degrade and become obsolete long before the content does.
• Migration (format renewal): Converting files from an aging or at-risk format into a current, well-supported one so the content stays openable as software changes.

A healthy program does both, on different schedules.

How often to refresh storage

Treat media refresh as a continuous, monitored process rather than a one-time event. Practical triggers include:

• A storage system or media type approaching the end of its supported life.
• Routine integrity checks (fixity, using checksums) detecting errors or drift.
• Vendor end-of-support, warranty expiration, or a planned hardware refresh cycle.

Many organizations refresh active storage every few years as part of normal IT lifecycle management, while maintaining multiple geographically separate copies so no single failure causes loss.

How often to migrate formats

Migration is driven by format risk, not the clock. Review your formats periodically (an annual or biennial review is common) and migrate when:

• A file format is becoming obsolete or losing software support.
• You can move from a proprietary format to an open, well-documented one.
• A standard you rely on is superseded.

Favoring open, widely adopted formats up front reduces how often migration is needed.

Build it into ongoing management

Sound digital preservation combines several habits: keep multiple copies in different locations, run regular fixity checks, monitor media and format health, and document every action so the chain of custody and authenticity remain defensible. Recognized guidance such as ISO 16175 on managing records in digital environments and the Library of Congress digital preservation program describes these practices in depth.

The core principle: data loss is prevented by continuous stewardship, not by waiting for a fixed deadline. Schedule reviews, automate integrity monitoring, and act when a trigger appears.

For related guidance, see the archives and preservation topic hub.