Due to space constraints at our Kew site, some of The National Archives’ collection is held offsite at DeepStore in Cheshire.
About DeepStore
DeepStore is a storage facility located at the Winsford salt mine in Cheshire. The environmental conditions and large amount of available space makes it a useful location for document storage.
We aim to send the least popular series offsite to minimise inconvenience to readers. Despite containing 30% of TNA’s holdings, orders from DeepStore accounted for just under 4% of public productions in 2024 to 2025.
Find out more about our use of DeepStore on our blog.
Viewing records held at DeepStore
You can order documents kept at DeepStore and view them in our reading rooms at Kew. Orders for offsite documents must be placed at least four working days in advance.
Digitised records
Most items that have been digitised are sent to DeepStore. This allows us to better preserve the originals whilst still providing public access to the digitised copies.
As they are available online, digitised records cannot be ordered to view in our reading rooms. However, if there is an issue with a scan of a document you can request to view the document in person using our records and research enquiry form.
Current DeepStore moves
It is usual for a document that is being moved offsite to be unavailable for about a month from the date of packing. We aim to have documents unavailable for no longer than six weeks.
These are series that have recently been collected for transfer to DeepStore. This list is updated monthly and reflects moves for the previous month:
| Series | First Piece | Last Piece | Date packed | Available to order? | Comments |
| CO 721 | 1 | 118 | 07/04/25 | No | |
| DO 11 | 1 | 262 | 10/04/25 | No | |
| DO 15 | 1 | 66 | 14/04/25 | No | |
| DO 19 | 1 | 77 | 14/04/25 | No | |
| DO 23 | 1 | 100 | 15/04/25 | No | |
| IR 90/10 | 21 | 62 | 16/04/25 | No | |
| AT 154 | 1 | 4867 | 28/04/25 | No |
This table was last updated: 30/04/2025
Upcoming DeepStore moves
These are series that have been flagged for transfer to DeepStore in the foreseeable future:
- AT 154
- LD 5 (closed)
- E 167
- DO 32
- DO 75
Get in touch
For any further questions about ordering and viewing documents that have been sent to DeepStore, please contact our Access and Advice team.