New York City Tax Block Boundaries

TAX_BLOCK_POLYGON data contains polygon-based spatial data representing the shape, location, and identity of Tax Blocks for New York City's Digital Tax Map. It is produced by the NYC Department of Finance and updated monthly, with data extracted on the last Friday of each month. The dataset includes columns for borough, block number, section number, and geometry.

Use Cases

• Visualize and analyze property density and distribution by aggregating data using the BORO and BLOCK columns.
• Perform spatial joins with other city datasets using the_geom polygons to correlate tax blocks with infrastructure or demographic data.
• Track historical changes in block boundaries by cross-referencing the VOLUME_NUMBER and SECTION_NUMBER with the official Digital Alteration Book.
• Identify potential data discrepancies or overlaps between tax blocks by flagging records where EOP_OVERLAP_FLAG or JAGGED_ST_FLAG is set.

Strengths

• Updated monthly with a documented refresh cycle, ensuring regular updates.
• Provides official, polygon-based boundaries (the_geom) for city tax administration.
• Includes a redundancy system with alternating Set A and Set B releases to ensure reliability.

Limitations

• Specific row count and total geographic area covered are unknown.
• Data may not reflect the latest changes from other city systems, such as exemptions or buildings data, as noted in the disclaimer.
• Sample data is unavailable, preventing assessment of data completeness and value distribution.

Provenance

Source

New York City Department of Finance Digital Tax Map Collection.

Collection Method

Extracted from DOF’s internal system and published via ArcGIS Online feature servers.

Freshness

Updated monthly; data extracted on the last Friday of each month and refreshed online on the 1st.

Geography

New York City, as indicated by BORO column.