The Create/Update Importer Identity Form (CBP Form 5106) is the form used to create or update importers' unique identification information within CBP's systems, per 19 CFR 24.5. CBP is currently in the process of revising the form and incorporating those changes into ACE and will post information about the updates being made to the 5106 on this webpage.
CBP Form 5106 Information
Frequently Asked Question
Importer Account (CBP Form 5106) Webinar Recording
ACE CATAIR: Create/Update Importer Identity Form
ACE 5106 Error Dictionary
Create/Update Importer Identity Form (CBP Form 5106)
Other CBP Form 5106 Resources
ACE 5106 Information Notice
5106 Policies and Procedures Guide
https://www.cbp.gov/trade/programs-administration/entry-summary/cbp-form-5106