HL7 Integration Solutions — Taction Software
Home/Blog/HL7 ADT A07 Message
HL7 MessagingADT · A07 Inpatient to Outpatient

HL7 ADT A07 Message: Change an Inpatient to an Outpatient

By Taction Software·October 22, 2026·6 min read
750+
HL7 integrations delivered
12+
Years in healthcare IT
30+
EHR platforms integrated
100%
HIPAA-compliant delivery

HL7 ADT A07is the HL7 Version 2 trigger event used to change a patient's status from inpatient to outpatient. It communicates a change in patient classification without necessarily indicating that the patient has been discharged or that a new encounter has been created.

The corresponding reverse event is ADT A06: Change an Outpatient to an Inpatient. A07 is important for hospital registration, electronic health records, patient accounting, billing, and revenue cycle management systems.

What Is an HL7 ADT A07 Message?

A07 tells connected systems that an admitted patient has been reclassified as an outpatient while their episode of care continues. It belongs to the HL7 ADT event family and is processed mainly through the patient class in PV1-2.

FieldDetails
Event CodeA07
Message TypeADT
Event NameChange an Inpatient to an Outpatient
Typical MessageADT^A07^ADT_A06
Important SegmentPV1
Important FieldPV1-2, Patient Class
Related EventADT A06
Example Patient ClassO for Outpatient

HL7 ADT A07 Message Example

MSH|^~\&|HIS|HOSPITAL|EHR|MAIN|20261022160000||ADT^A07^ADT_A06|MSG07001|P|2.5
EVN|A07|20261022155500
PID|1||MRN070001^^^HOSPITAL^MR||SMITH^JOHN||19850412|M
PV1|1|O|OPD^ROOM1^BED1

In this example, PV1-2 = O identifies the patient's updated outpatient classification. The receiving application must also reconcile the existing encounter and any financial or administrative consequences according to the interface agreement. All patient information is fictional.

Explore each segment and its key fields:

Illustrative ADT^A07 — HL7 v2.5 (fictional data)

Select a segment to see what it carries

MSH — Message Header

Required

MSH identifies HIS as the sender and EHR as the receiver. ADT^A07^ADT_A06 identifies the inpatient-to-outpatient change; A07 shares the ADT_A06 structure with A06.

FieldMeaningValue in this message
MSH-3Sending applicationHIS
MSH-5Receiving applicationEHR
MSH-9Message typeADT^A07^ADT_A06
MSH-10Message control IDMSG07001
MSH-12HL7 version2.5

How A07 Works in Healthcare Systems

An A07 event is sent when a patient is no longer classified as admitted but continues receiving care during the same episode. The updated location belongs in PV1-3, and the previous location, when different, belongs in PV1-6. The interface agreement determines whether the account continues or a new account is opened.

Because a class change can affect billing and census, receivers should apply it to the existing encounter rather than creating a new visit. Our HL7 v2 integration services cover these patient-class workflows.

Important HL7 A07 Fields

FieldDescription
MSH-9ADT^A07^ADT_A06
EVN-2Event recorded date and time
PID-3Patient identifier
PID-18Current patient account number
PV1-2Updated patient class, typically O
PV1-3New assigned patient location
PV1-6Prior patient location
PV1-19Visit number
MRG-3Optional prior account number when applicable

Field-level rules for patient class, location, and account number should be documented in the interface specification. Our HL7 parsing and data mapping team can help define them.

A07 vs A06 vs A03

EventMeaning
A06Change outpatient to inpatient
A07Change inpatient to outpatient
A03Discharge or end a visit

A07 should not automatically close the patient's encounter. The receiving system must apply the agreed patient-class and account-handling rules. To end a visit, the sender uses an A03 discharge instead.

Mirth Connect A07 Filter

var messageType =
    msg['MSH']['MSH.9']['MSH.9.1'].toString();

var triggerEvent =
    msg['MSH']['MSH.9']['MSH.9.2'].toString();

var structure =
    msg['MSH']['MSH.9']['MSH.9.3'].toString();

var patientClass =
    msg['PV1']['PV1.2']['PV1.2.1'].toString();

return messageType === 'ADT' &&
       triggerEvent === 'A07' &&
       structure === 'ADT_A06' &&
       patientClass === 'O';

The filter assumes the agreed interface uses O for outpatient. Production processing should additionally validate patient and encounter identifiers, sender authorization, account-handling rules, and the applicable HL7 profile. Mirth Connect development services can help implement this.

Frequently Asked Questions

What is HL7 ADT A07?

ADT A07 is the HL7 event for changing an inpatient to an outpatient. It updates the patient's admission classification while the patient may continue receiving care.

Is A07 the same as discharge?

No. A07 changes the patient's classification. A03 communicates discharge or end of visit.

Which HL7 field changes during A07?

PV1-2 is the primary patient-class field. Other fields, including patient location, account number, and visit number, may also change according to the implementation.

What is the message structure for A07?

In HL7 v2.5, the message is ADT^A07^ADT_A06. A07 shares the ADT_A06 message structure with A06.

Need HL7 ADT A07 Integration?

Taction Software provides HL7 ADT interface development, Mirth Connect integration, EHR connectivity, and patient administration workflow automation. Explore our HL7 interface messaging services and EHR and EMR integration services.

ShareLinkedInXEmail

Need an HL7 ADT A07 Interface Built or Fixed?

Tell us your registration system, receiving applications, HL7 version, and how patient class and accounts are handled. Our engineers will scope PV1 mapping, encounter handling, Mirth Connect channels, and acknowledgments for your workflow.

  • Free 30-minute technical consultation
  • A07 patient class and ACK review
  • NDA available upon request
  • Response within 24 hours

Talk to an HL7 Expert

Share your ADT^A07 interface requirements and our team will respond within 24 hours.

Loading verification…