The 911 Emergency Response System initiated the conversion of older rural addresses to modern, urban-styled addressing in the 1980's. The purpose was to generate a faster response by accurately associating a physical address with the telephone number making the emergency call to the authorities. The USPS recognized that mailers would improve their deliverability by obtaining this new address data and so created the Locatable Address Conversion System (LACS).
Rural, PO Box, Highway and other non-unique address types are compared to the USPS master conversion file. Addresses in your file that have undergone a permanent conversion are updated.
After running this service, you will receive a result file containing your original input file with the new, corrected data appended to it. Fields are added to your record to store updated addresses. A summary report provides you with statistical data describing your results and a record layout defines field positioning and content.




0.1-3% Range.
Improve your LACSLink™ match results by also running Address Standardization & Correction and the National Change of Address (NCOALink™) service.
*Please note that following our file format specifications is required only for our Self-Service products.
Please see our File Format Specification page for more information on required input and standard result fields.
Locatable Address Conversion System (LACSLink™) service also appends the following field:
R = RR (Rural Route)
X = RR W/BOX
H = HC (Highway Contract)
V = HC W/BOX
<blank> = STREET
This column contains the date of the LACS conversion (YYYYMM).
Y = LACS Updated
N = Not LACS Updated
2 = RR/HC with box number to street type address (individual match)
3 = Street to street type address, split * (individual match)
5 = RR/HC with box number to street type address (address match)
7 = Street to street type address, non-split (address match)
8 = RR/HC with no box number to street type (individual match)
DSF2 processing is provided by a nonexclusive licensee of the United States Postal Service. The prices for NCOALink and DPV services are not established, controlled, or approved by the United States Postal Service.