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Address verification software that improves deliverability and reduces errors

Stamps.com address verification checks every street address against the USPS database before you print. With CASS-certified technology, you verify an address, standardize the address format, and append ZIP+4 so labels scan cleanly and arrive on time.

Address verification screen

Send with confidence, speed, and accuracy

With automated USPS address validation inside your workflow, you reduce undeliverables, speed up delivery, and control spend without extra steps or extra tools.

Fewer errors and returns

Catch typos, bad ZIP code entries, and non-standard abbreviations before a label is created. By validating each street address against the USPS service database, you prevent wasted postage and avoid packages bouncing back. Cleaner data in means successful deliveries out.

Faster, more reliable delivery

Standardization matters. Stamps.com upgrades five-digit ZIPs to ZIP+4, normalizes abbreviations to USPS-preferred formats, and improves scan accuracy so shipments move through USPS postal operations with fewer exceptions. That means faster routing and predictable arrival times.

Save time and money automatically

Verification happens before you print. There is no separate address verification tool to manage and no add-on charge. Set it once and ship at scale with consistent, USPS-approved results across every order.

Built-in capabilities that verify every address and standardize every label

Everything you need to check address validity, standardize output, and keep fulfillment moving is built into Stamps.com. These features work together to improve address matches and label quality across your entire address list.

CASS-certified USPS address validation

  • Validate every destination against the USPS Address Matching Service using CASS-certified software. When an address doesn’t match, suggested corrections appear instantly so you can print the right label the first time. Use it as your everyday address validation tool inside Stamps.com to check address validity without leaving your workflow.
    Compares address matches to the USPS database
  • Suggests corrected spelling and formatting
  • Ensures USPS-preferred standards are met before label creation

Automatic ZIP+4 completion and standardized address format

  • Only have a five-digit ZIP code? Stamps.com appends the proper ZIP+4 and normalizes abbreviations to USPS standards for cleaner labels and faster routing. This address validation tool helps your labels scan cleanly and move through sorting with fewer exceptions.
    ZIP+4 appended for precision
  • Abbreviations normalized to USPS standards
  • Standardized, machine-readable address format for reliable delivery

Always-current USPS data, synced into Stamps.com

  • Our system regularly syncs with the USPS Address Matching Service so you are checking against the most current, deliverable address information. List-wide cleansing is included at no extra cost, giving you consistent, accurate output across shipments.

    Continuous alignment with the USPS service database

  • Cleanses every address list at no additional charge
  • Produces uniform labels that improve sort accuracy

Set it and forget it with automated checks

  • Enable verification once and let Stamps.com do the work in the background as teams print. No separate login, no manual batch process, and no need to copy data between systems. You get address validity at the moment of label creation, so operations keep moving.
    Runs automatically during label creation
  • Eliminates manual rework and data transfers
  • Scales from single labels to high-volume batches

Real-world time and cost savings

  • Accurate addresses drive measurable improvements in on-time delivery and reduce return handling. Expect fewer customer contacts for wrong addresses, fewer replacement shipments, and a drop in postage waste caused by undeliverables.
    Cuts undeliverables and return processing
  • Improves customer satisfaction through on-time arrivals
  • Reduces spend tied to re-shipments and wasted postage

Simple for every team to use

Because verification is built into Stamps.com, your support, operations, and warehouse teams use the same address verification tool across channels. That consistency shortens training, reduces errors, and keeps your brand experience tight from checkout to delivery.

Example: from messy to mailable

Before:

  • John Smith
    11950 Salam Drive
    Granada Hils, Ca 91333
  • After verification:
    John Smith
    11950 Salem Dr
    Granada Hills CA 91344-2347
    This is the power of automated corrections, USPS address validation, and ZIP+4 in action.

Frequently asked questions about shipping address verification

What exactly does “address verification” do in Stamps.com?

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It compares each destination to the USPS Address Matching Service using CASS-certified software, flags issues like misspellings or bad ZIP codes, and suggests the USPS-approved version before you print a label.

How does ZIP+4 improve deliverability?

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If you only have a five-digit ZIP, we append the correct ZIP+4 and standardize street and state formats so labels scan cleanly and sort faster through USPS operations—helping packages move without exceptions.

Is this built in, or do I need a separate tool?

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It’s built into Stamps.com. Addresses are cleansed and verified automatically before labels or postage print—no extra software to manage.

Does it cost extra to cleanse my address list?

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No. Stamps.com cleanses every address on your list at no additional charge as part of the label creation process.

How current is the USPS data you use?

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Stamps.com regularly syncs with the USPS Address Matching Service Database so your labels reflect the most current, deliverable information available.

What happens if an address can’t be verified?

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When the software detects an issue, it offers the USPS-approved alternative—much like a spell checker—so you can correct and print with confidence.

Can this reduce returns and wasted postage?

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Yes. By catching typos, non-standard abbreviations, and incorrect ZIP codes before printing, you can prevent undeliverables, avoid postage waste, and improve on-time delivery.

Is “address cleansing” the same as “address verification”?

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They work together. CASS-certified cleansing and verification standardize formatting and confirm deliverability against USPS data, ensuring addresses meet USPS-preferred specs.

Do you standardize the address format on my labels?

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Yes. Abbreviations are normalized to USPS standards and labels are formatted consistently for machine readability and faster routing.

Will this help my direct mail or marketing campaigns?

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Standardized, verified addresses help more mail get delivered, which can improve response rates and customer experience by speeding delivery.

Deliver every package right the first time.

With Stamps.com’s built-in address verification, you can print labels that meet USPS standards, eliminate costly delivery errors, and keep every shipment on schedule—automatically. Start verifying addresses today and see how much time, money, and hassle you can save.