BAR^P01 — Add Patient Accounts

The message that creates a financial patient account in the hospital billing system. Pivot between admission, billing and insurance coverage.

Purpose of the message

BAR^P01 is sent when a new financial patient account is created — typically at admission, when starting an outpatient file, or to open an inpatient stay. It carries:

• unique financial account identifier (PID-18 = Account Number);
• patient identity (PID);
• associated visit (PV1);
• admission diagnoses (DG1);
• financial guarantor (GT1);
• applicable insurance coverages (IN1 / IN2 / IN3);
• known allergies (AL1);
• billable procedures (PR1);
• accident context if any (ACC).

BAR^P01 is the trigger event for hospital encounter accounting: once sent, the billing system can start posting procedures, supplies and days against the account. For outpatient flows, BAR^P01 is often followed by DFT^P03 for each financial unit transaction.

Segment structure

BAR_P01
  MSH                    Message Header (mandatory)
  EVN                    Event Type (mandatory)
  { PATIENT
      PID                Patient Identification (mandatory)
      [ PD1 ]            Patient Additional Demographics
      { VISIT
          PV1            Patient Visit
          [ PV2 ]
          [ { ROL } ]    Role
          [ { DB1 } ]    Disability
          [ { OBX } ]
          [ { AL1 } ]    Allergy Information
          [ { DG1 } ]    Diagnosis
          [ DRG ]        Diagnosis Related Group
          [ { GT1 } ]    Guarantor
          [ { INSURANCE
              IN1        Insurance
              [ IN2 ]
              [ { IN3 } ]
              [ { ROL } ]
            } ]
          [ { ACC } ]    Accident
          [ { UB1 } ]    UB82 / UB92 billing data
          [ { UB2 } ]
          [ { PR1 [ { ROL } ] } ]   Procedures
        }
    }

MSH — EVN

• MSH-9: BAR^P01^BAR_P01.
• EVN-1: P01 (trigger event).
• EVN-2: account creation date/time.
• EVN-5: account-creating user (XCN).

PID — PV1

Patient identity and visit. See ADT^A01. For BAR^P01 specifically:

• PID-18: Patient Account Number — the key field of BAR. Unique financial account identifier (not the durable patient identity, which is PID-3).
• PID-19: SSN (US-only, deprecated in v2.5+).

DG1 — Diagnosis

Diagnoses tied to the account:

• DG1-3: diagnosis code (typically ICD-10).
• DG1-6: diagnosis type (table 0052: A = Admitting, W = Working, F = Final).

GT1 — Guarantor

Financial guarantor (the person or entity responsible for payment). Key fields:

• GT1-3: guarantor name.
• GT1-5: address.
• GT1-6: home phone.
• GT1-7: work phone.
• GT1-11: relationship to patient (table 0063: SE=Self, SP=Spouse, FA=Father…).
• GT1-19: guarantor SSN.

IN1 — Insurance

Insurance information per coverage. For patients with primary + secondary, carry multiple IN1 (with IN1-1 = sequence number).

• IN1-1: sequence number (1 = primary, 2 = secondary).
• IN1-2: insurance plan (CE).
• IN1-3: insurance company ID.
• IN1-4: insurance company name.
• IN1-8: group number (employer group).
• IN1-12: effective date.
• IN1-13: expiration date.
• IN1-16: subscriber name.
• IN1-17: subscriber relationship (table 0063).
• IN1-36: policy number / member ID.

PR1 — Procedures

Procedures already tied to the account. At admission, may be empty; for BAR updates (P02), list of procedures pending billing:

• PR1-3: procedure code (CPT, CCAM, ICD-10-PCS).
• PR1-5: procedure date/time.
• PR1-6: procedure minutes.

Real example

Creation of an inpatient account for John Doe, admitted as emergency for myocardial infarction (ICD-10 I21.9), with Aetna PPO as primary insurance, penicillin allergy on file, two initial procedures (visit + CPR):

MSH|^~\&|HIS|HOSP01|BILLING|HOSP01|20260514163000||BAR^P01^BAR_P01|MSG00009999|P|2.5.1
EVN|P01|20260514163000|||USER001^Smith^John^^^DR.
PID|1||MRN567890^^^HOSP^MR||DOE^JOHN^A^^MR.||19720515|M|||100 MAIN ST^^ANYTOWN^CA^90210^USA||(555)555-1234|||S||ACCT2026-9999|123-45-6789
PV1|1|I|ICU^101^A^HOSP01|EM|||DRSMITH^Smith^James^A^^DR.|||CAR|||1|||DRSMITH^Smith^James^A^^DR.|ADM|VIP||||||||||||||||||HOSP01|||||20260514102530
DG1|1||I21.9^Acute myocardial infarction, unspecified^I10|||F||||||||||DRSMITH^Smith^James^A^^DR.
GT1|1||DOE^JOHN^A^^MR.||100 MAIN ST^^ANYTOWN^CA^90210|(555)555-1234||19720515|M||SE^Self^HL70063||123-45-6789
IN1|1|AETPPO^Aetna PPO Standard^HL70072|AETNA1234|AETNA|^^^Aetna Insurance Center^Hartford^CT^06156|||GRP-2026-ACME|ACME|||20260101|20261231||SE^Self^HL70063|DOE^JOHN^A^^MR.|18^Self^HL70063|19720515|100 MAIN ST^^ANYTOWN^CA^90210|||1|W123456789
AL1|1||PEN^Penicillin^L|MO||19850714
PR1|1||99213^Office visit, level 3^CPT||20260514102530|1
PR1|2||92950^Cardiopulmonary resuscitation^CPT||20260514103000|1
ACC|||A01|MV^Motor Vehicle^HL70050

• EVN — P01 event, created by USER001 (Dr Smith).
• PID-18 — Patient Account Number ACCT2026-9999.
• DG1 — Acute myocardial infarction (ICD-10 I21.9), final diagnosis.
• GT1 — patient is self-guarantor (SE).
• IN1 — Aetna PPO Standard GRP-2026-ACME, period 1 Jan - 31 Dec 2026.
• AL1 — penicillin allergy (PEN), moderate, since July 1985.
• PR1 1-2 — CPT 99213 (visit) + CPT 92950 (CPR).
• ACC — accident A01, Motor Vehicle type.

Acknowledgement

The billing module acknowledges with ACK^P01:

MSH|^~\&|BILLING|HOSP01|HIS|HOSP01|20260514163001||ACK^P01^ACK|ACK00009999|P|2.5.1
MSA|AA|MSG00009999

Common errors

• Missing PID-18 — without Patient Account Number, the account cannot be created on the billing side. It's the central field of BAR.
• IN1-1 not incremented — for patients with primary + secondary, two IN1 segments must have IN1-1=1 and IN1-1=2. Otherwise, the secondary is ignored or overwrites the primary.
• DG1 without DG1-6 (Type) — a diagnosis without a type (Admitting / Working / Final) cannot drive DRG billing.
• Missing GT1 — without a guarantor, the billing module does not know who to bill for the residual balance. For a self-pay patient, set GT1 with GT1-11=SE.
• Forgotten allergies — including an AL1 in BAR is essential to avoid double data entry; otherwise, the EHR loses information.
• PR1 with inconsistent minutes — PR1-6 (minutes) must reflect the actual procedure duration, especially for time-based billing (anaesthesia, physiotherapy).

Related BAR events

FHIR equivalent

In FHIR R5, BAR^P01 maps to a transaction-type Bundle containing multiple resources:

• PID → Patient
• PV1 → Encounter
• PID-18 → Account (Account.identifier)
• DG1 → Condition (with category=encounter-diagnosis)
• GT1 → Account.guarantor + RelatedPerson
• IN1 → Coverage
• AL1 → AllergyIntolerance
• PR1 → Procedure
• ACC → Encounter.reasonReference to Condition (with category=accident)

See also DFT^P03 for the unit financial transactions following BAR^P01, and Claim for the final billing in FHIR.