A safe deposit box is a secure container in a bank vault. Customers rent it annually to store valuables: jewelry, documents, heirlooms, backup hard drives. The bank provides the vault, the box, and the security. The customer provides the key and the contents. The bank does not know what is inside, and it does not insure the contents.

The process is straightforward. The customer signs a lease agreement, provides identification, and pays the annual fee, typically $50 to $200 depending on the box size. The bank issues a key. To open the box, the customer signs in, presents identification, and uses their key along with a bank key to unlock the box. Some banks use biometric verification. The customer takes the box to a private booth to access the contents. The bank records each entry.

Safe deposit boxes are not insured by the FDIC. The FDIC insures deposits, not box contents. If the bank fails, the contents are safe, but the customer may need to retrieve them from the acquiring bank. If the box is burglarized, the bank is not liable unless it was negligent. Customers should insure valuable contents separately through a rider on their homeowners or renters policy.

Safe deposit box use has declined. Fewer people rent them, and some banks have stopped offering them. But for documents that are hard to replace and items with sentimental value, a safe deposit box remains a sensible option.