Entry Type 13 is now live in ACE PROD, giving eligible international mail shipments an electronic informal entry pathway within the Automated Commercial Environment. Customs brokers and mail-channel filers should treat the September 22, 2026 launch as both a technology change and a compliance workflow transition requiring disciplined EDI validation, exception management, and production monitoring.
What the Entry Type 13 Production Launch Changes
A New Electronic Pathway for International Mail
Entry Type 13, formally identified as Informal Mail Entry, supports merchandise entering through the international mail process. It creates an alternative electronic informal entry pathway for qualifying mail shipments and connects U.S. Postal Service international mail data with ACE entry processing.
The functionality reached the ACE Certification environment on July 24, 2026, allowing software providers and participating filers to test message construction, response handling, and operational workflows. It moved into ACE PROD on September 22, 2026, through the INT-057 and CBP-290 system enhancements.
Production availability does not mean every low-value or postal shipment automatically qualifies for Entry Type 13. Participation and shipment eligibility remain subject to the conditions of the test. Brokers, importers, and technology providers should validate those conditions before routing transactions through the new entry type rather than relying on assumptions based on value, transportation mode, or prior mail-processing practices.
Production Deployment Does Not End the Test
Entry Type 13 remains a test even though it is available in the production environment. The test commenced on September 22, 2026 and is expected to continue until CBP modifies, concludes, or formalizes the process. Comments may generally be submitted throughout the test using the designated subject line, Comments on the Entry Type 13 Test.
That status matters operationally. Message requirements, error conditions, participation rules, and processing behavior may evolve as CBP evaluates transaction data and stakeholder feedback. Compliance teams should assign ownership for monitoring changes and translating them into system configurations, standard operating procedures, customer guidance, and staff training. A one-time production release project is unlikely to be sufficient for a test environment that may continue to mature.
EDI Requirements Brokers and Filers Need to Address
Aligning Cargo Release, Entry Summary, and Manifest Data
Entry Type 13 implementation has direct EDI implications. Filers should use the current ACE CATAIR materials for Cargo Release and Entry Summary, together with the applicable manifest implementation guidance, to map data elements and understand message relationships. Development teams should avoid adapting another informal entry workflow merely by changing the entry type code; the mail channel can introduce distinct data dependencies and validation requirements.
The implementation review should identify which data originates with the postal shipment record, which information must be supplied by the filer, and how values move between manifest, cargo release, and entry summary processes. Particular attention should be paid to identifiers, party information, merchandise descriptions, country data, classification inputs, value fields, and any data used to establish admissibility or calculate duties and fees.
A field-level mapping document is essential. It should identify the source system, required format, validation rule, transformation logic, responsible party, and downstream use for every transmitted element. This creates a defensible bridge between customs requirements and the actual software configuration.
Build Around Condition and Error Codes
The applicable ACE condition and error codes should be incorporated into automated response handling rather than treated as technical reference material used only by developers. Each response should lead to a defined operational outcome, such as automatic correction, manual review, customer outreach, escalation, or suspension of the filing.
Testing should include both successful and unsuccessful scenarios. Teams should intentionally submit incomplete, inconsistent, duplicated, and incorrectly formatted transactions in an approved testing environment to confirm that errors are captured and routed properly. They should also test amendments, cancellations, status updates, retries, and responses received out of sequence.
Organizations that did not complete certification testing before the production launch should use a controlled rollout. A limited transaction population, enhanced review thresholds, and real-time monitoring can reduce the risk of scaling an unproven integration across the entire mail-entry operation.
Operational Readiness for Informal Mail Entry Processing
Establish Controls Before Increasing Volume
Entry Type 13 affects more than transmission logic. Brokers and mail-channel filers need controls governing intake, eligibility validation, classification, valuation, admissibility screening, release monitoring, and record retention. Existing informal entry controls may provide a foundation, but they should be evaluated specifically against international mail data and the conditions of the test.
A practical workflow should confirm that the shipment is within the permitted scope before transmission. When eligibility cannot be established, the transaction should move to an exception queue rather than defaulting into Entry Type 13. The workflow should also preserve the basis for the filing decision, including the data received, validations performed, user actions taken, and messages exchanged with ACE.
Low-value volume can magnify small weaknesses. A mapping error affecting one field may produce hundreds or thousands of rejected transactions, while an overly permissive rule may allow questionable entries to proceed without review. Automated validation should therefore be paired with targeted human oversight based on risk indicators, data quality, customer history, commodity type, and error frequency.
Monitor Production Performance and Compliance Outcomes
Post-deployment monitoring should cover both technical and compliance metrics. Useful measures include acceptance rates, rejection rates, correction frequency, response times, unresolved exceptions, manual touches per entry, and recurring error codes. Compliance teams should also track classification changes, valuation issues, admissibility holds, and shipments redirected to another entry process.
Daily monitoring is generally appropriate during the initial production period. Technical, brokerage, and compliance personnel should review recurring failures together because an ACE rejection may reflect a mapping defect, missing customer data, a misunderstood requirement, or an underlying compliance issue.
Change management should remain active throughout the test. Any revision to implementation guidance, validation rules, or operating conditions should trigger an impact assessment. The organization can then determine whether it requires code changes, configuration updates, regression testing, revised procedures, or customer communication. Maintaining a formal decision log will help demonstrate that changes were evaluated and implemented consistently.
Frequently Asked Questions
What Is Entry Type 13?
Entry Type 13 is an electronic Informal Mail Entry process for qualifying merchandise entering through the international mail channel. It gives eligible participants an alternative way to submit informal entry data through ACE using U.S. Postal Service international mail shipment information. It should not be treated as a universal entry option for all postal or low-value shipments.
When Did Entry Type 13 Become Available in ACE PROD?
Entry Type 13 became available in the ACE production environment on September 22, 2026. The related capabilities were available in the ACE Certification environment beginning July 24, 2026, giving filers and software providers an opportunity to test their integrations before production deployment.
Is Entry Type 13 a Permanent ACE Entry Process?
It is currently operating as a test. Production deployment enables live filing but does not convert the process into a permanent program. CBP may generally adjust the test based on operational results and stakeholder feedback, so participants should continue monitoring requirements and maintaining flexible system configurations.
Which Technical Materials Should Filers Review?
Filers should review the current ACE CATAIR Cargo Release and Entry Summary materials, the applicable manifest implementation guidance, and the relevant condition and error codes. Technical teams should confirm that they are working from the versions applicable to Entry Type 13 rather than relying on mappings developed for other informal entry types.
Can Every International Mail Shipment Use Entry Type 13?
No. Availability in ACE PROD does not establish eligibility for every international mail shipment, every low-value transaction, or every filer. Participation and transaction eligibility depend on the conditions of the test. Organizations should validate scope before filing and route uncertain or ineligible shipments to an appropriate alternative process.
How Stable Software Can Help
Turn Entry Type 13 Requirements Into a Controlled Workflow
Entry Type 13 introduces new integration, validation, and exception-management demands for customs brokers and mail-channel operators. Stable Software helps trade organizations connect customs data, automate filing workflows, apply configurable compliance controls, and manage ACE responses without relying on fragmented spreadsheets or manual handoffs.
A well-designed platform can validate incoming shipment data, route eligibility exceptions, preserve filing histories, monitor rejection patterns, and support controlled updates as the test evolves. These capabilities help brokerage and compliance teams improve throughput while retaining the visibility needed to manage risk. Learn how Stable Software can support scalable customs operations and ACE integration.
