The HCAD GIS files contained on this page/CD are in Environmental Systems Research Institute's
shapefile format. They can be accessed using any of ESRI's ArcGIS products, including
ArcExplorer 2505.  This page/CD contains everything required to use ArcExplorer Desktop 2505 for Windows.
For more information, Please see the ESRI web site at
Note: For Unix/Linux users, you can download ArcExplorer 3 Java Edition at

The projected coordinate system for the data is
State Plane of South Texas (Zone 4204) and Datum NAD 1983.


The "parcels" shapefile contains polygons for every parcel of real property in the
county. Parcels.shp Attribute Field Definitions:

HCAD_NUM -- text (length 13): Unique 13-digit real property account number. Use this field to "join" to real data files.
BLK_NUM -- text (length 20): 
LOT_NUM -- text (length 20): 
CONDO_FLAG -- text (length 1): Value of 1 means stacked, otherwise value is 0.
Denotes if a parcel is stacked (duplicated onto itself). HCAD uses stacked parcels
for condos and undivided interest accounts as well as pure accounts.
(A pure account is a new account built for a special taxable value in an individual jurisdiction.)

Note the above fields are only populated for NEW accounts added since October 2004.
A Harris County Appraisal District account number (HCAD_NUM) is attached to each
property which will allow an individual to link detailed property information (also
available from to every parcel.  See "Joining GIS to Real Property data" below.

The "row_anno" shapefile contains right-of-way text for Harris county.


"Joining GIS to Real Property data":

Joining GIS shapefile to Access MDB tables required 3rd party GIS software,
such as ArcGIS Desktop ArcMap from ESRI, some GIS aptitude and database relationship knowledge.

GIS parcel shapefile can be joined directly to the Access tables (see below) using the
"HCAD_NUM" field (13 characters) in parcel.shp and the "Account_Number" field (13 characters)
in the Access tables.  For example, if you want to join real property parcel information,
you would join the "Account_Number" field in the Real_Acct.mdb Access Database to the "HCAD_NUM" field in the
parcel shapefile.

Please read the instructions provided on
for information on how to get the Access database populated with data from the text files.
Specifically, The Data Import Instructions