Phase 4 Collection of Post-2020 Census Congressional and State Legislative District Plans / Non-Partisan Liaisons

Dear Liaison,

Thank you for participating in the U.S. Census Bureau’s collection of the 120^th Congressional District (CD) and/or updated (2026) state legislative district (SLD) plans. We have inserted the plans you submitted into our Master Address File/Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) System will use these boundaries to tabulate future data and geographic products.

To confirm that your updates have been accurately inserted into our system, please review the materials attached to this email and verify their accuracy. The materials include:

• Whole Block Equivalency Files.

  • Listings of all 2020 census tabulation blocks in your state and the district to which they are assigned. Split blocks are assigned to a single district as requested by the Census Bureau and identified by you during the original submission.

    • Format is comma-delimited text.

    • Fields are: <Edit sub-bullet as appropriate for the plans that were submitted>

• For CDs: State, County, Tract, Block, and CD.

• For SLDs: State, County, Tract, Block, SLDU, SLDL, SLDU Name, and SLDL Name.

• Split Block Listing file.

  • Listing of all split blocks that were originally submitted.

• Shapefiles.

  • Contain all the edges within a county submitted with split blocks.

    • Edges that split blocks between districts are identified with an “S” in the CBBFLG field. There may be multiple records for the same split if the split has multiple segments.

  • Contain the district shapefiles for <insert CD/SLDs plans> that contained split blocks.

If the verification materials correctly represent your districts, please complete the attached verification form(s) to certify your agreement. If anything is inaccurate, please use the same form(s) to identify the needed corrections. Please email the form(s), and any other supporting materials, to the Redistricting and Voting rights Data Office at your earliest convenience, but no later than <two weeks from send date>. If we do not receive a response by <insert date>, we will assume that the representation of districts is correct.

If you have any questions, please contact the Redistricting and Voting rights Data Office (RVDO) at 301-763-4039 or at <rdo@census.gov>.

Sincerely,

<RVDO staff name>

Attachments

Block equivalency file(s)

Split block listing file

Phase 4 Verification Form – CDs <Edit/Include as appropriate>

Phase 4 Verification Form – SLDs <Edit/Include as appropriate>