UB04 Field 64: Document Control Number

Overview

Field 64 on the UB-04 claim form is designated for the Document Control Number (DCN). According to CMS guidance, this field is Situational — it is not required on every claim but must be completed when the health plan or its fiscal agent has assigned a control number to the original bill as part of their internal control system ^[1]. The DCN serves as a unique identifier that links the claim to the payer’s internal tracking records, facilitating reconciliation and audit trails. The Maryland Medicaid UB-04 instructions list FL 64 as “Document Control Number (DCN)” without additional detail, confirming its standard placement on the form ^[2]. A separate CMS transmittal (R1915CP) reiterates that FL 64 is situational, meaning its use depends on payer requirements or specific billing circumstances ^[3]. Because the DCN is not universally mandated, providers must verify with each payer whether a DCN is expected and, if so, what format or source number to enter.

When to Use

Field 64 should be completed only when the health plan or its fiscal agent has issued a Document Control Number for the original bill. CMS explicitly defines the field as situational: “The control number assigned to the original bill by the health plan or the health plan’s fiscal agent as part of their internal control” ^[1]. This means that if the payer does not provide a DCN, the field should be left blank. Therefore, providers should consult each payer’s billing instructions. The Maryland Medicaid instructions list FL 64 without specifying mandatory use, implying that it is only required when the state’s fiscal agent assigns a DCN ^[2]. CMS R1915CP also marks the field as situational, reinforcing that it is not a universal requirement ^[3]. Failure to include a required DCN may result in claim rejection or processing delays.

Step-by-Step Claim Example

Consider a hospital submitting a UB-04 claim to a commercial health plan that uses a fiscal agent. The provider has received a prior payment and now needs to submit a corrected claim (type of bill 117). The original claim was assigned a DCN of “1234567890” by the fiscal agent. Step 1: Locate Box 64 on the UB-04 form. According to the CMS definition, this field is for the control number assigned to the original bill by the health plan or its fiscal agent ^[1]. Step 2: Enter the DCN exactly as provided by the payer — in this case, “1234567890”. Do not add spaces, hyphens, or prefixes unless specified by the payer. Step 3: Verify that the DCN matches the number on the original claim. If the corrected claim is for a different patient or service, a new DCN may be required. Step 4: Complete all other required fields. Note that FL 64 is situational; if the payer does not require a DCN, leave it blank ^[3]. Step 5: Submit the claim. The payer’s system will use the DCN to link the corrected claim to the original, ensuring proper adjustment of payments. The Maryland Medicaid instructions list FL 64 among standard fields, confirming its placement on the form ^[2]. This example illustrates the typical use case: a corrected or replacement claim referencing an original DCN.

Common Mistakes & Audit Red Flags

One frequent error is entering a DCN when none was assigned. Because FL 64 is situational, populating it with a random number or a provider-generated control number can cause claim mismatches. CMS states the DCN is “the control number assigned to the original bill by the health plan or the health plan’s fiscal agent” ^[1]. Using an incorrect or fabricated number may lead to the claim being rejected or processed against the wrong original bill. Another mistake is omitting a required DCN on a corrected or voided claim. If the payer’s instructions mandate the DCN for adjustments, leaving the field blank can result in the claim being treated as a new submission, causing duplicate payments or denials. Providers should always check payer-specific billing guides; the Maryland Medicaid instructions list FL 64 without mandatory language, but other payers may require it ^[2]. Audit red flags include inconsistent DCNs across multiple submissions for the same patient encounter, or DCNs that do not match the payer’s format (e.g., too many digits). CMS R1915CP confirms the situational nature, so auditors will look for evidence that the DCN was either correctly supplied when needed or appropriately omitted ^[3]. Additionally, transposing digits in the DCN can cause the claim to link to a different original bill, leading to payment errors. To avoid these issues, always copy the DCN directly from the payer’s remittance advice or prior claim acknowledgment, and never re-use a DCN from a different patient or service.

Related Codes/Fields

The following table lists UB-04 fields that are commonly associated with control numbers, authorization codes, or payer identifiers, as referenced in the Maryland Medicaid UB-04 instructions ^[2]. These fields often interact with or are confused with the Document Control Number.

Field Number	Field Name	Relationship to FL 64
FL 63	Treatment Authorization Code	Used for prior authorization numbers; distinct from DCN which is for internal payer control.
FL 51	Health Plan Identification Number	Identifies the specific health plan; DCN is a claim-level control number.
FL 54	Prior Payments – Payer	Records prior payments; DCN may be needed to reference the original claim for adjustments.
FL 50	Payer Name	Identifies the payer; DCN is assigned by that payer or its fiscal agent.
FL 52	Release of Information Certification Indicator	Certification indicator; not a control number but part of the claim header.
FL 53	Assignment of Benefits Certification Indicator	Another certification; no direct link to DCN.
FL 65	Employer Name (of the Insured)	Situational field; DCN is unrelated to employer information.

These fields are listed in the Maryland Medicaid UB-04 instructions, which include FL 64 as part of the standard form layout ^[2]. Providers should ensure that when a DCN

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References

[1] CMS Chapter 25 — FL 64 — https://www.cms.gov/regulations-and-guidance/guidance/manuals/downloads/clm104c25.pdf

[2] Maryland Medicaid — FL 64 — https://health.maryland.gov/mmcp/provider/Documents/ffs-billing/UB04-Hospital-Billing-Instructions%20%281%29.pdf

[3] CMS R1915CP — https://www.cms.gov/Regulations-and-Guidance/Guidance/Transmittals/downloads/R1915CP.pdf