All legal boundaries and names are as of January 1, 2023. The 2023 TIGER/Line Shapefiles were released on November 22, 2023.

The following national-scale layers have been included this year: CBSA, CSA, and METDIV.  The following layers are gone permanently and are no longer maintained by the Census Bureau: CNECTA, NECTA, and NECTADIV.

For the 118th Congressional District shapefiles, all legal boundaries and names are as of January 1, 2020, with the exception of the 118th Congressional Districts and the State Legislative Districts, which are as of January 1, 2023. A special county layer for the state of Connecticut is included with boundaries and names as of January 1, 2022 for reference purposes because the counties in this state have been significantly changed since 2020.

The 118th Congressional District Shapefiles are based on the whole 2020 Census tabulation block representations of the 118th Congressional District plans as submitted by the states to the U.S. Census Bureau.

In instances where plans included split 2020 Census tabulation blocks, two shapefiles are provided, one that represents the whole block plan, and one that represents the split block plan.

Only one state--Colorado--split blocks in their 118th Congressional District plan. Three states split blocks in their 2022 State Legislative District- Upper Chamber (SLDU) and State Legislative District- Lower Chamber (SLDL) plans: Colorado, Minnesota, and North Dakota. Additionally, Delaware split a block in their 2022 SLDU plan, and Pennsylvania split a block in their 2022 SLDL plan.