UB04 Condition Codes Code 57: SNF Readmission

Overview

Condition Code 57 is a UB-04 claim form indicator meaning "SNF readmission within 30 days" ^[1]. It is used to identify a skilled nursing facility (SNF) readmission that occurs within 30 days of a prior discharge from the same or another SNF. This code is part of the standard condition code set maintained by the Centers for Medicare & Medicaid Services (CMS) and is listed among the codes published by Noridian Healthcare Solutions for Medicare Part A claims ^[1]. The UB-04 claim form is the standard paper claim form used by institutional providers, including acute inpatient hospitals and SNFs, as described in the MassHealth UB-04 Billing Guide ^[2]. Condition Code 57 is entered in Fields 18–28 of the UB-04, which are designated for condition codes ^[2]. Proper use of this code helps payers identify readmissions that may be subject to special payment rules, such as the SNF prospective payment system (PPS) readmission adjustment.

When to Use

Condition Code 57 should be used when a patient is readmitted to a skilled nursing facility within 30 days of a prior discharge from any SNF ^[1]. The 30-day window is calculated from the date of the prior discharge to the date of the new admission. This code applies regardless of whether the readmission is to the same SNF or a different facility. It is also used when the readmission is for a related or unrelated condition, as the code only indicates the timing of the readmission ^[1]. Providers must ensure that the prior discharge date is documented in the patient’s record and that the readmission date falls within the 30-day window. The code is entered in Fields 18–28 of the UB-04 claim form ^[2]. Failure to use this code when applicable may result in claim denials or incorrect payment adjustments. Medicare and other payers use this code to apply readmission penalties or to adjust the SNF PPS payment rate ^[1].

Step-by-Step Claim Example

A patient is discharged from Sunnyvale SNF on March 1. On March 20, the same patient is readmitted to Sunnyvale SNF for a urinary tract infection. The SNF billing department prepares a UB-04 claim for the new stay. In Fields 18–28 (Condition Codes), the biller enters "57" to indicate a SNF readmission within 30 days ^[1]. The claim also includes the patient’s demographic data, admission date (March 20), discharge date (to be determined), and all applicable revenue codes and charges. The biller verifies that the prior discharge date (March 1) is documented in the medical record. The claim is submitted electronically or on paper using the UB-04 form ^[2]. The payer’s system recognizes Condition Code 57 and applies the appropriate SNF readmission adjustment. The claim is processed and paid according to the readmission policy. If the readmission had occurred on April 2 (32 days after discharge), Condition Code 57 would not be used because the 30-day window is exceeded ^[1].

Common Mistakes & Audit Red Flags

One common mistake is using Condition Code 57 for readmissions that occur more than 30 days after discharge. The code is explicitly defined as "SNF readmission within 30 days" ^[1]. Another error is failing to include the code when the readmission is within the 30-day window, which can lead to overpayment or audit findings. Providers sometimes confuse Condition Code 57 with Condition Code 55 ("SNF bed is not available") or Condition Code 56 ("Medical appropriateness condition code (SNF)") ^[1]. Audit red flags include inconsistent use of the code across multiple claims for the same patient, missing documentation of the prior discharge date, and claims that show a readmission within 30 days but do not include Code 57. Payers may also flag claims where the readmission is coded as a new stay without any condition code, as this could indicate an attempt to avoid readmission payment adjustments. Providers should ensure that all SNF readmissions within 30 days are consistently coded with Condition Code 57 and that supporting documentation is retained ^[1].

Related Codes/Fields

The following table lists condition codes from the Noridian set that are related to SNF billing or readmission scenarios ^[1]. These codes are entered in Fields 18–28 of the UB-04 claim form ^[2].

Code	Meaning	Relevance to SNF Readmission
55	SNF bed is not available	Indicates a barrier to admission, not a readmission code
56	Medical appropriateness condition code (SNF)	Used when SNF stay is medically appropriate; may accompany readmission
57	SNF readmission within 30 days	Directly identifies a readmission within 30 days
58	SNF patient terminated MA Plan enrollment	Indicates a change in coverage, not a readmission trigger
16	SNF transition exemption	Payer-only code for SNF transition billing rules
40	Same day transfer	May apply if readmission occurs on same day as discharge

---

References

[1] Noridian Condition Codes — https://med.noridianmedicare.com/web/jea/topics/claim-submission/condition-codes

[2] MassHealth UB-04 Guide — https://www.mass.gov/doc/ub-04-billing-guide-0/download