How long does a credit report last after you die?

Credit agencies like any large organization that collects data will have a data archiving process. Archived data is stored in a less accessible but retrievable state. Financial data especially is stored for long periods of time to lessen any legal exposure. Some data is transferred to a permanent media and never destroyed. The period of time from when data is recorded and data is destroyed depends on the organization storing the data. There are often laws to set up minimums, but the data is the property of the organization.

As for the person associated with the data being deceased, most companies take great care in dealing with how the data of the deceased is used. However it probably has little bearing on the archiving and destruction of related data.