What is NCOA? National Change of Address Processing, Explained
NCOA stands for National Change of Address — a USPS-licensed database of address change records filed by U.S. residents and businesses when they move. Mailing list providers run their data against this file to update or remove records before delivering a list. It is one of the most important accuracy steps between a raw database and a list you can confidently mail.
Every LeadsPlease list is NCOA-processed and CASS Certified before download. Build a targeted mailing list →
What is NCOA?
When someone moves in the United States, they can file a change-of-address form with the USPS. The USPS collects these records and makes them available — under license — to authorized data providers through a program called NCOALink. The database contains tens of millions of move records and is updated weekly.
NCOA processing is the step where a mailing list is compared against that database. When a match is found — meaning a name and address on the list belongs to someone who filed a change of address — the list provider can update the record to the new address, or flag it for removal if no forwarding address is available.
How NCOA Processing Works
The process runs automatically as part of list preparation. Here is what happens between the raw database and your download:
Address standardization (CASS)
Each postal address is first standardized against the USPS address database — formatting, ZIP+4 codes, carrier route codes, and deliverability status are all confirmed. This is the CASS step (see below).
Name + address matching against NCOALink
Each record is compared against the NCOALink database using a combination of first name, last name, and address. The match logic is fuzzy — it accounts for name variations and minor address differences — to catch as many genuine moves as possible without false positives.
Address update or suppression
If a match is found and a new forwarding address is available, the record is updated to the new address. If a match is found but no forwarding address was filed (the person moved without notifying the USPS, or the forwarding window has closed), the record is flagged or removed depending on the provider's process.
Deceased suppression
Alongside NCOA, most providers also run records against deceased suppression files. LeadsPlease applies deceased suppression on every order — records for individuals confirmed deceased are removed before delivery.
48-month NCOA vs. 18-month NCOA
The USPS stores change-of-address records in the NCOALink database for 48 months from the date of the move. Some providers only process against the most recent 18 months of moves. Full 48-month processing catches more outdated records — particularly useful for older list segments or annual mailing programs where records may have been sitting in a file for over a year.
NCOA vs. CASS: What's the Difference?
These two terms appear together often, but they do different things:
| Process | What it checks | What it fixes |
|---|---|---|
| CASS Coding Accuracy Support System | Is this address real and correctly formatted? | Standardizes street address format, corrects ZIP codes, adds ZIP+4 and carrier route codes, flags non-deliverable addresses |
| NCOA National Change of Address | Has the person at this address moved? | Updates records to new forwarding address; suppresses records where no forwarding address is available |
Think of it this way: CASS confirms the address exists and is deliverable. NCOA confirms the person you're trying to reach still lives there. Both steps together are what backs a high postal deliverability guarantee.
Why NCOA Matters for Your Campaign
Every undeliverable piece in a direct mail campaign costs you money twice: once in postage and printing, and once in the missed opportunity to reach that prospect. At scale, the impact adds up fast.
Wasted print and postage
A list with 5% bad addresses on a 10,000-piece campaign means 500 pieces printed and mailed to no one. At $0.60/piece all-in, that's $300 of pure waste — before accounting for the opportunity cost.
USPS postage discounts
USPS bulk mail rates require CASS-certified address processing. Using NCOA-processed, CASS-certified lists keeps you eligible for the discounted postage rates that make direct mail economics work.
Accurate response rate measurement
If your list has 8% undeliverable addresses, your real response rate is higher than it appears — some of your "non-responders" never received the piece. Clean data gives you accurate numbers to optimize from.
Brand impression
Mail delivered to a previous resident reflects on your business. A piece addressed to "John Smith" at a home he sold three years ago signals to the new occupant — and to anyone John Smith knows — that your data is out of date.
How LeadsPlease Uses NCOA
Every list order from LeadsPlease is processed against the USPS NCOA file and CASS Certified before you download. You do not need to submit your list for separate processing — it happens automatically as part of every order.
- NCOA processing: Applied to every postal mailing list order against the current 48-month NCOALink file
- CASS Certification: All postal addresses standardized and validated with USPS CASS Certified software
- Deceased suppression: Applied on every order — records for confirmed deceased individuals are removed
- 30-day database refresh: The underlying LeadsPlease database is updated every 30 days, so the source records you're starting from are current before NCOA is even applied
- 98%+ accuracy guarantee: If postal deliverability falls below 98% on your list, LeadsPlease will credit or replace the undeliverable portion
Ready to Build a Clean, NCOA-Processed Mailing List?
Every LeadsPlease list is NCOA-processed, CASS Certified, and backed by a 98%+ accuracy guarantee. Instant counts and transparent pricing — no subscription required.
Build a Mailing ListFrequently Asked Questions
What does NCOA stand for?
NCOA stands for National Change of Address. It refers to the USPS-licensed database of address change records filed by U.S. residents and businesses when they move, and to the process of running a mailing list against that database to update or remove outdated records.
How often is the NCOA database updated?
The USPS updates the NCOALink database weekly. Change-of-address records remain in the file for 48 months from the date the move was filed. LeadsPlease processes every list against the current NCOA file at the time of order.
What is the difference between NCOA and CASS?
CASS (Coding Accuracy Support System) validates and standardizes the format of each postal address — confirming the street, city, state, and ZIP code are real and correctly structured. NCOA then checks whether the person at that address has moved. CASS answers "is this address deliverable?" — NCOA answers "does this person still live there?" Both are applied to every LeadsPlease postal list order.
Does LeadsPlease process lists against NCOA?
Yes — automatically on every postal list order. You do not need to submit your list for separate processing. NCOA, CASS certification, and deceased suppression are all applied before your list is available to download. The result is backed by a 98%+ postal deliverability guarantee.
What happens to records that fail NCOA processing?
If a match is found and a current forwarding address is available, the record is updated to the new address. If a match is found but no forwarding address was filed — meaning the person moved but did not submit a forwarding request to the USPS, or the 48-month window has closed — the record is flagged or suppressed. You receive a cleaned list, not the raw output.
Does NCOA apply to email lists?
No. NCOA is specific to postal (physical mail) addresses. Email list accuracy is maintained through a separate verification process — LeadsPlease email records are verified for deliverability before download. If you need both postal and email addresses for the same contact, LeadsPlease records include both, and each data type is cleaned through its respective process.