Nationwide Interoperability

The National Interoperability (NIOP) Committee

The NIOP committee is dedicated to activities and programs that advance the goal of national electronic tolling interoperability, promoting the objectives of allowing motorists to use a single account to pay tolls across North America. The NIOP Committee is comprised of IBTTA members representing toll operators, tolling coalitions, technology companies, and third-party service providers, and also welcomes participation from non-IBTTA members.

The NIOP Committee currently has four standing subcommittees:

NIOP Business Rules and Interface Control Documents (ICD)
Customer Service
Marketing & Communications
Road-user Charging

The Committee also has an active work program striving to incorporate third-party providers more seamlessly into toll payments and account management options available to motorists. The Committee is led by Chair Tracie Brown of the Central Texas Regional Mobility Authority along with Vice Chair Vinny Valdez of The Corridor Agencies.

NIOP Support Documents and Information

National Interoperability (NIOP) Business Rules and Interface Control Document ICD and other documentation can be found below.

Modified Business Rules

(March 2026: New Update)

Modified NIOP Business Rules for EZIOP and CUSIOP Interoperability (January 2026)

Current Version: Business Rules & ICD Version 2.0

(March 2026: New Updates)

National Interoperability (NIOP) Business Rules, Version 2.0

Business Rules for National Interoperability Version 2.0 FINAL (2023-05-01)
Business Rules for National Interoperability – Appendix A – Reports Version 1.00 FINAL (2023-05-01)

National Interoperability (NIOP) Interface Control Document (ICD):

NIOP ICD Version 2.1

National Interoperability Interface Control Document (ICD) Version 2.1 (2025-12-31)

NIOP ICD Version 2.0

National Interoperability Interface Control Document (ICD) Version 2.0 (2023-05-01)
NIOP ICD Appendix A (Released 2018-11-26) - Hub IDs
NIOP ICD Appendix B (Released 2026-02-19) – Away NIOP Agency ID (New)
NIOP ICD Appendix C (Released 2026-03-05) - NIOP Tag Agency ID (New)
NIOP ICD Appendix D (Released 2025-12-03) - NIOP Tag Validation List Schedule
NIOP ICD Appendix E (Released 2026-02-17) – License Plate Type (New)
NIOP Appendix F - State Codes (Released 2023-05-01)

NIOP ICD Appendices are updated regularly and are identified by the release date.

Prior Versions: Business Rules & ICD Version 1.2

National Interoperability (NIOP) Business Rules Version 1.01

NIOP Business Rules (Version 1.01 Final Released 20190507)

National Interoperability (NIOP) Interface Control Document (ICD) Version 1.2

NIOP ICD Version 1.02 Final Released 2019-05-07)
NIOP ICD Appendix A (Released 2018-11-26)
NIOP ICD Appendix B (Released 2022-09-16)
NIOP ICD Appendix C (Released 2022-09-16); NIOP ICD Appendix C (Released 2023-12-19) - NIOP Tag Agency IDs
NIOP ICD Appendix D (Released 2022-11-3)
NIOP ICD Appendix E (Released 2019-02-01)

NIOP Agency ID Assignment and Coordination (2021-04-05)

2016-2018: Resources

2018

Interoperability: Towards the New Frontier(link is external) (ITS International)

2017

An overview of the IBTTA efforts to achieve National ETC Interoperability

In May 2017 IBTTA finalized the test plan describing the methodologies and procedures to be used in conducting the Phase 2 NIOP protocol performance testing. The following documents describe both the test approach and the plan methodologies. This plan was developed in consultation with both toll operators and the technology manufacturers. The goal of the plan is to accomplish the following:

Provide statistically sound NIOP testing results at 80% confidence
Stage and prioritize tests to minimize cost and duration
Limit test cases to those that involve variables that are expected to impact results
Where possible, maximize testing in a lab setting
Test Planning – Statistics and Test Strategy Approach
NIOP Phase 2 – Parts 1 and 2 Test Plan

2016

Resolution On Interoperability Next Steps as adopted by the IBTTA Board on January 8, 2016
Update on IBTTA's effort to achieve nationwide interoperability of electronic toll collection systems (September 2016)

2014-2015: Resources

Status on Interoperability – Subcommittee on Transportation and Public Assets of the U.S. House Oversight and Government Reform Committee (September 28, 2015). Below are copies of testimony and related documents.

Watch Video of Hearing: [Part 1(link is external)]; [Part 2(link is external)]
Patrick Jones, Executive Director (on behalf of IBTTA)
Tom Knuckey, Member of the IBTTA Interoperability (IOP) Steering Committee and Chair, IBTTA Roadside Operations Subcommittee (on behalf of the IBTTA IOP Committee)
JJ Eden (on behalf of the Alliance for Toll Interoperability (ATI)
Andrew Fremier (on behalf of the California Toll Operators Committee (CTOC)
Diane Gutierrez-Scaccetti (on behalf of Florida's Turnpike Enterprise/FDOT), Miami-Dade Expressway Authority and Tampa-Hillsborough Expressway Authority
P.J. Wilkins (E-ZPass Interagency Group)
Jeffrey Lindley (Federal Highway Administration, U.S. DOT)
IBTTA issued RFP for consulting and technical services that support the testing, certification and selection of the National Interoperability (NIOP) protocol. View RFP // RFP FAQ
Toll Operators Nomination Letter
Supplier Sponsorship Letter | Attachment 1 – Traceability Matrix

2014

Board Briefing on Subcommittee Activities: