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Data Hygiene

Data hygiene is critical to ensuring accurate and powerfully targeted data that strengthens any direct-marketing campaign.

The first step to properly clean and update addresses requires marketers to run their files through a file conversion process. File conversion processes are designed to identify potential problems within the records and prepare the files for higher match rates and maximum results during the data hygiene processes. The primary purpose of the conversion is to isolate all name and address attributes. It can also identify problem records that may affect the deliverability of the mail piece.

After all files are converted and all quality-control measures have taken place, the files are ready to be processed through address hygiene programs.

These are the steps we available to increase deliverability of you file(s):


Combines multiple files and identifies and reduces duplicates, which lowers mail costs.

Address Coding:

Address coding standardizes and verifies addresses, corrects ZIP codes, ZIP+4 Delivery Point codes and carrier route codes. Based on the input file makeup, the rate of records that are verified and corrected during the address coding process are consistently in the mid to high 90 percent range. This process increases postal qualification and reduces overall postal expense. In addition, address coding also increases match rates for change of address processing and identifies more duplicates, during the merge/purge process, resulting in an overall ‘cleaner’ mail file.

Delivery Point Validation:

Delivery Point Validation (DPV) provides the highest level of address accuracy checking.

  • What is DPV? – The Postal Service DPV database is essentially a “yes/no” table for checking the validity of any known individual house, apartment, Post Office Box, rural box, mail drop or commercial address that receives mail.
  • How does it work? – The DPV System assists mailers in obtaining accurate delivery address information and facilitates identification of erroneous addresses contained in mailer address files. Mailer use of DPV will help to reduce the amount of undeliverable as addressed (UAA) pieces, which in turn will result in more efficient postal mail processing and delivery operations.
  • Why is it better then pulling ZIP+4 alone? – Without DPV, the ZIP+4 database is only capable of confirming whether addresses fall within the “low to high” address ranges specified in ZIP+4 records. For example, “1 to 49 (odd) Main Street” may be a standard house number range listed in the ZIP+4 database and any odd house number in that range will match that ZIP+4 record, whether or not the address is a valid Postal Service Delivery Point.

    With DPV, you can confirm whether any individual address is a valid delivery point, regardless of what the ZIP+4 database range implies. If only five addresses exist in a given range like “1 to 49 (odd)”, DPV will validate the five known addresses and reject any other address in the range.

    In other words, a ZIP+4 database can only determine a candidate ZIP+4 for an address. Utilizing both ZIP+4 and DPV databases, allows you to determine whether the address is a valid delivery point and produce valid ZIP+4 codes.

Second Generation Delivery Sequence File (DSF2):

DSF2 is a highly versatile processing tool that can be used for address hygiene, as a resource in the merge/purge process or as a tool to obtain deeper postage discounts. DSF2 provides high quality address matching and is the most accurate tool to help move toward 100 percent Zip+4 bar coding as mandated by the USPS. It also appends address specific information such as seasonal addresses, vacant addresses and address type (single vs. multi family dwelling, commercial, etc.) enabling better targeting requirements. With a unique feature that allows a single name to be added, one can maximize postal discount by automatically adding names to carrier routes when counts have fallen short. Names can be dropped to exclude marginal nonperforming names when discounts are not advantageous.

Locatable Address Conversion System (LACS):

Utilizing LACS, one can convert all rural format addresses (RR/Box #) on a file to standard street grid addresses (123 Main St.), ensuring more deliverable and cost-effective mailings.

Change of Address Service:

A full range of USPS-licensed and proprietary change of address services are available to remove outdated addresses and standardize deliverable addresses for your client’s mailings.

Address Correction and Apartment Append:

With this process, the non-ZIP+4 coded records are matched against multiple external databases in an attempt to ZIP+4 code more records. Generally, 20 percent to 40 percent of the non-ZIP+4 coded records are able to be correctly ZIP+4 coded using this process.

Apartment append adds or corrects an apartment number to records identified by USPS files as having a missing or invalid apartment number. Additionally, Apartment Append ensures that these records are accurately matched against the NCOA file and that mail pieces are delivered to the intended recipient.

Request a quote or give us a call today to speak with one of our experienced appending solution specialists. Get the most from your customer files by using Dunhill Data Hygiene Services.

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