The Geographic Reference Files (GRFs) are state-based pipe-delimited text files. They are produced in two types - Codes and Names - that may be used together.

The Geographic Reference File – Codes (or GRF-C) provides census block-level geographic codes for the current entities in the Census Bureau's Master Address File/Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) System as of the year of the file. Each row in the file represents a single census block, with suffixes to indicate if the block has been split since the 2020 Census. Attribute columns provide the geographic area codes associated with each block. These files use '9' fills for some columns if the block is not within that geographic entity type.

The Geographic Reference File – Names (or GRF-N) provides additional information, such as names and selected attributes, for the geographic entities whose codes appear in the GRF-C. Each entity appears as its own row within this file, and empty columns should be expected.

Please see the record layouts for the GRFs for additional explanation.