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Fuels Registration, Reporting, and Compliance Help

How to Report Attest Engagements

Below is a step-by-step process for submitting attest engagements per Title 40 CFR Part 80 Subpart F.

Follow these steps to report.

STEP 1: Determine whether the submitter has access to report.

A user must be registered and assigned the proper roles to submit attest engagements.

For more information, see: How to Become a Delegated User of a Registered Company in OTAQREG (PDF) (4 pp, 352 K, June 2018, EPA-420-B-18-032, About PDF)

STEP 2: Determine deadlines.

Attest engagements are submitted annually.

For more information, see: Reporting deadlines for Fuel Programs

STEP 3: Read general instructions for all attest engagements.

Title 40 CFR Part 80 Subpart F contains attest procedures related to the qualifications of the attest auditor, applicable definitions, guidelines for sample sizes, and reporting and record retention requirements.

Include the following information:

  • The four digit EPA Company ID and name
  • If attest engagement is specific to an individual facility (i.e., gasoline refinery), include the five digit facility ID and name

EPA publishes updated registration information, including ID numbers, at

For more information, see: 40 CFR Part 80 Subpart F

STEP 4: Read program-specific instructions.

In addition to the general instructions, each program has specific instructions.

For more information, click the tab above or go to: Program-specific instructions for attest engagements

STEP 5: Submit attest engagements through EPA's Central Data Exchange.

To submit a file electronically, read this user guide:  User guides for OTAQDCFUEL in CDX

For instructions on how to submit attest engagement, see: How to Manage Attest Engagement Submissions in OTAQREG (PDF) (13 pp, 953 K, September 2018, EPA-420-B-18-041, About PDF).