Public employer Fontana Unified School District (FUSD) has hired Third-Party Administrator (TPA) Athens Administrators to handle its workers’ comp claims, effective January 1, 2026.

Previously, FUSD self-administered its claims for injured employees. Now, providers should submit all bills for the treatment of FUSD employees to Athens. Crucially, Athens is not changing FUSD claim numbers.

FUSD’s switch is likely good news for providers. Athens uses bill review vendor accūrō Solutions, which, as daisyNews previously reported, proactively helps ensure its clients’ payment compliance.

FUSD Billing Details

Providers should submit all FUSD bills, supporting documents, and Second Review appeals to Athens as of January 1, 2026, regardless of the date of service. Providers should also direct all billing inquiries to Athens.

Again, Athens has not assigned new claim numbers to existing FUSD claims.

For providers who are (wisely) billing electronically (e-billing), the FUSD e-billing Payer ID is CB184. For providers mailing bills to FUSD, the mailing address for Athens is:

Athens Administrators
PO Box 696
Concord, CA 94522

As always, we strongly recommend e-billing. Payment speeds are drastically faster (9.4 days on average for our clients), the provider maintains proof of submission, and there is a far lower chance of bills or supporting documents being lost or ending up “not on file.”

For Athens specifically, daisyData show that over 99,466 daisyBill client’s bills, Athens maintained an Electronic Data Interchange (EDI) “Grade” of B+, issuing payment in just 10 working days on average.

daisyBill experts are here to help providers, whether or not they are clients. If you have questions about billing FUSD specifically or how to navigate California workers’ comp billing generally, use the pink chat icon in the bottom right of this screen or email us at info@daisybill.com.

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