SIMFOR utilizes Microsoft Access (Access 97+) to store all non-map based information. Databases are created in MS Access; further data entry and editing can be accomplished directly within the SIMFOR interface (SIMFOR includes a blank Access database from which databases can be built using the interface). Data may also be edited in Access, though this is recommended only for advanced users - due to the relational nature of the data, a database could become corrupt if one table is altered without updates made to other dependent tables. The SIMFOR interface provides a user-friendly environment for managing databases and changing model parameters.

There are three main types of data required for use with SIMFOR: map data, curve data and schedule data. All three data types are specific to the given planning area and are provided by the user.