NCOALink® - Details

How NCOALink works

NCOALink service is offered by licensees of the USPS. The source of the NCOALink data is a permanent Change of Address (COA) filed by the relocating postal customer. Approximately 40 million of these COAs are filed annually. The NCOALink database is updated weekly with this information and changes are kept in the file for four years.

Data from permanent change of address cards from the entire country is transmitted to the USPS National Customer Support Center. (Temporary moves are not carried on the NCOALink database.) The data is compiled, edit checks are performed, and data is relayed weekly to licensees, which operate under a non-exclusive license of the USPS. Your list is standardized, the ZIP + 4® code is added and then compared with the data on the NCOALink file. Address change information is provided to you when your customer's name and address information matches the name and address information on the NCOALink database.

Each record contains the relocating Postal customer's name along with an old and new address. The old address is compared to the NCOALink customer's list for matching purposes and the new address is returned, if a match is made, to the customer. The typical profile of the new address information contained on the NCOALink file is as follows:

  • 80.92% are forwardable moves (Contain address information)
  • 1.18% are unconfirmed new addresses - new address not provided
  • 13.8% are moved, left no forwarding address
  • 3.92% are PO Box closed
  • 0.18% are foreign moves

Change of Address information is controlled by strict name and address matching logic. To make the best use of the information returned from the NCOALink process, it is best to understand the NCOALink matching logic. All matches made to the NCOALink file require an exact match on address. The required name matching is determined by the move type on the NCOALink file. The NCOALink file is composed of approximately 40% family moves, 54% individual moves, and 6% business moves.

Move Types and Name Matching Requirements are as follows:

  • Individual Move: A match on first name, middle name/initial, surname and title is required. Gender is checked and nickname possibilities are considered.
  • Family Move: Also referred to as a household move. This requires a match on surname only.
  • Business Move: This requires a match on business/firm name.

When possible, postal customers who move multiple times within the four-year period are linked, or chained, to ensure that the latest address is furnished when an NCOALink match is attained. This is not always possible if subsequent COAs are not filed in exactly the same manner as COA filed previously. (e.g., if move types are different - e.g. Family and Individual - they will not be chained)

Benefits and monetary payback of NCOALink

The NCOALink service is an excellent mail list management tool. In most cases the NCOALink service is by far the most cost effective way to obtain change of address information. The NCOALink service provides the following benefits to mailers:

  • NCOALink processing helps ensure prompt delivery at the most current mailing address.
  • NCOALink processing helps reduce these mailing expenses:
    • Printing
    • Postage
    • Address Correction Charges
    • File Maintenance
    • Mail Processing

The payback from the NCOALink service typically ranges from 200% to 300% of the cost on the first mailing. The total payback can be many times that. The payback you receive may be higher or lower depending on a number of factors including:

  • Average age of the address information.
  • Quality of the name and address information.
  • Demographic profile.
  • Cost and weight of the pieces being mailed.
  • How often the list is mailed?
  • How the list would be maintained if NCOALink processing was not done?
  • How the list will be used and maintained after NCOALink processing is done?
  • If the mail is advertising for a product or service, the quality of the offer and the profitability of the sale.
  • If the mail pieces are requests for donations, the generosity of the people who have moved.

Limitations of NCOALink

NCOALink is a good service, but it is not a complete mail list cleanup system. You can receive address changes through the NCOALink service that are not available in other ways, and there are changes you will not receive from NCOALink processing. Whether or not you receive new address information from NCOALink processing depends on a number of factors, a few of which include: the relocating postal customer must have filed a change of address; the relocating postal customer must provide accurate information that corresponds with your data; the length of time since the change of address was filed; etc. Also, the demographic and geographic makeup of your list and the quality of the data in your list will affect the results of the NCOALink processing. You may want to use other methods to find the address changes that NCOALink processing doesn't provide.

What can go wrong?

You may not receive a ZIP + 4 Code for some addresses. Usually ZIP + 4 match rates run in the 85% to 93% range. The match rate is different for each list and can run from 0% to 100%.

And why?

  • The data submitted may not be precise enough to narrow the address down to a single ZIP + 4 area. (e.g., "125 MAPLE" is submitted and both "125 N MAPLE ST" and "125 S MAPLE ST" are valid addresses in two different ZIP + 4 areas.)
  • The data submitted is not sufficiently standard for that area. (e.g., "1010 CENTENNIAL BLDG" is submitted where the Postal Service® recognized address is "125 E 3RD ST SUITE 1010".)
  • The data submitted by the local Post Office is not complete.

What can go wrong?

You may receive an incorrect ZIP + 4 Code and incorrectly standardized address. For most lists this is a rare occurrence but it is not uncommon on business lists that have many vanity addresses.

And why?

  • The data submitted is not standard for the intended destination but similar to that for another destination. (e.g., "1010 PILLSBURY CTR" (Pillsbury Center is a building and the suite number is 1010), is submitted and "1010 PILLSBURY DR" falls within the same ZIP.)

What can go wrong?

You may not receive change of address information when someone has actually moved. NCOALink processing will yield new addresses for many of the people and companies that have moved and filed address changes with the USPS, but some will be missed. The information you receive from NCOALink processing will depend on the accuracy of the name and address information on your file and the information filed by the relocating postal customer.

And why?

  • The name and address you submitted may be substantially different than the address change filed by the addressee. (e.g., The addressee submitted a change as "MARY G. SMITH-JONES", "125 MAPLE ST APT 125" and you submitted "M SMITH", "125 MAPLE ST". In this example, the last name, middle initial or address will cause a miss.)
  • Addressee may not have filed a change of address with the USPS.
  • When mail carriers submit "Move - No Forwarding Address" cards they rarely have complete information. (See above)
  • The addressee may have moved too recently to appear on the NCOALink file. It takes 2-4 weeks for a change to appear on the NCOALink file.
  • The addressee may live in an area where the Postal Service has not yet automated the address change process.

What can go wrong?

You may receive a new address when the addressee has not moved. These tend to appear in small numbers on most lists.

And why?

  • Someone in a household filed a change of address incorrectly. (e.g., A child when moving out of parents' house submitted a "Change of Address" card indicating a family move.)
  • Someone filed a "Change of Address" with the old and new addresses in the wrong place on the card.

What can go wrong?

You may receive an incorrect new address when the addressee has moved. These tend to appear in small numbers on most lists.

And why?

  • Someone has moved multiple times during the 48 month timeframe and the moves could not be linked or chained. The NCOALink database will link multiple moves providing back the newest address as long as each move filed contains complete address information and all move types are the same. (e.g. If an apartment number is included in one move and omitted in the next move, the link cannot be made.)
  • Two moves are filed from the same household under the same surname, one family move and one individual move or two family moves. The incorrect new address may be returned, although matching requirements exist to prevent this.

Explanation of output record

The Output File:

  • A record layout for the standard NCOALink output file is provided with your media. It is important that you refer to this when using your output data.

Address Standardization and ZIP + 4 Coding:

  • The standardized data segment of the output record contains a standardized version of the input address data.
  • The standardized version of the address is usually as good as or better than the input address.
  • When no ZIP + 4 is found, we recommend that you do not use the standardized address information that is provided.
  • If you do not use the standardized version of a particular address, you should not use the standardized ZIP Code™ or ZIP + 4 Code (If changed) for that address either.
  • You may wish to perform special checks on addresses that have a ZIP Code change or substantial address change as these are most likely to have suffered from standardization.

Note on Representation of ZIP Codes:

All five digits of a ZIP Code are significant. Therefore, ZIP codes with fewer than five digits (e.g. "1234") are not valid as input. For most such records this will not cause a problem because the ZIP codes are normally verified by city and state information. To avoid this problem, store ZIP codes as Character or Text data rather than Numeric. (In spreadsheets this means Labels rather than Values.)

Change of Address Data:

The change of address segment of the output record contains information only if a record matches with the NCOALink database. The "Move Type" and "Deliverability Code" fields identify the type of match. If "M" is found in the "Deliverability Code" field, then new address information will be found in the appropriate fields in this segment.

Change of address information will generally not be found for all people on your list who have moved. While NCOALink processing matching criteria allows some close matching, most moves found are based on an exact match of your data to the NCOALink database. The match criteria is strict, therefore some moves that might be found manually by a mail carrier will not be found through NCOALink processing. Typically, between 25% and 50% of the moves filed with the USPS will be found through NCOALink processing. A small portion of the NCOALink return codes ("Moved - No Forwarding Address", "PO Box Closed" and "Foreign Move") will be found with NCOALink processing.

Strict matching criteria is in place to avoid inaccurate moves being returned to your file. However, it is possible, albeit rare, to get moves that did not actually take place. The following are some of the reasons this occurs:

  • Individual moves have been incorrectly filed as family moves by postal customers.
  • An individual incorrectly filed a permanent rather than a temporary move. (Temporary moves are not on the NCOALink database.)
  • Multiple moves with different move types have been filed to and from the same location. (e.g., An individual move is filed from point A to point B and then a family move is filed from point B back to point A. In this case, both moves would remain on the NCOALink database and the moves would not be "linked" or "chained".)
  • Company moves are based on close matching, so similar company names from the same address may result in incorrect moves. (e.g., If Forest Valley Motor Company and Forest Valley Meter Service were at the same address and one of them moved, it is possible that a move would be found for either company name.)

National Deliverability Index (NDI):

A National Deliverability Index (NDI) report is supplied for each list that is processed through the NCOALink service. This report will provide a uniform methodology for evaluating deliverability of address lists.


Enhanced Carrier Route postal discounts are available for mail files that meet density requirements and are sorted in either eLOT or walk sequence. eLOT sequencing is available through ZIP + 4 processing and walk sequencing is available through DSF processing. eLOT sorts mail by approximate carrier-casing sequence, while DSF2 places mail pieces in the same sequence that the mail carrier for that carrier route will deliver the mail. The postal presort necessary to receive these discounts requires additional processing. The NCOALink service will not presort a mailing list.

Individual Matching Logic in NCOALink

Individual logic is an option that is often used for name specific files, such as: financial statements, tax information, and voter registration lists. Using individual matching logic, all family and individual moves are treated as individual moves -- using all name components to match to the NCOALink database. This option will cause you to miss good moves, but avoid some of the bad moves as described in the following:

For Example: John Smith filed a Family move under his name from his old address. Jane Smith is listed on your file at the same old address. With standard logic, you would receive a new address for Jane because John filed a family move. With individual matching logic, you would not receive a new address for Jane. This example appears to be new address information you would want on your mail list, unless you consider the following scenario. If John is a student who accidentally filed a family move* by checking the wrong box or by not checking a box at all on the USPS Change of Address card; or if John and Jane have recently separated and moved to different locations. You may not want to change Jane's address to the new address.

* Individual Move is the default move type. If a box is not checked on the USPS Change of Address form, the move is considered an individual move.

To request Individual Matching, please select "Individual Logic" in section Output Options, #2- Matching