On January 25, 2026, the USPS is implementing changes to its Web Tools APIs. These updates affect how mailing systems interact with USPS services behind the scenes, including data exchange, validation, and service responses.
These changes are part of USPS’s ongoing effort to modernize its infrastructure and standardize how mail data is processed and returned to mailers and service providers.
For most organizations, this is not a visible change. Mail will continue to move. Timelines remain the same. The impact is operational, not conceptual.
Why This Matters
Any time USPS updates core systems, there is downstream impact for platforms that integrate directly with those services.
For organizations that rely on accountable mail, what matters is not just that mail is sent, but that proof, status, and retrieval remain accurate, timely, and defensible after the send. That means systems like ours need to be aligned with USPS changes as they occur, not after customers feel the effects.
This is normal operational maintenance is a regulated environment. It is also exactly why change management matters.
How ACi is Handling the Update
ACi has been tracking the USPS Web Tools changes and will implementing the required updates across our systems before the January 25 weekend.
Our approach is straightforward:
- Changes are being implemented in advance of the USPS cutover
- Systems will continue operating as expected during the transition with occasional brief access issues while updates are being implemented.
That said, any code change introduces the possibility of minor irregularities. These are typically small and short-lived, but awareness helps ensure they are addressed quickly.
What Customers Should Know
We do not expect disruption. Mailings, confirmations, and proof workflows should continue normally.
During the changeover window, customers should be attentive to their normal operational checks. If anything appears unexpected, delayed, or inconsistent, our support team should be notified as soon as possible so it can be reviewed in context.
Early visibility allows us to confirm whether what you are seeing is expected behavior during the transition or something that needs immediate correction.
The Bigger Picture
USPS changes are part of the operational reality of accountable mail. Systems evolve. Regulations shift. Proof requirements tighten.
ACi’s role is to absorb that complexity and keep your workflows defensible and operationally usable, even when the infrastructure underneath them changes.
If you have any questions ahead of the January 25 update, or if something doesn’t look right afterward, our team is ready to help.