HL7 GT1 Segment: Guarantor
The HL7 GT1 segment (Guarantor) identifies the person financially responsible for the patient’s account. It appears in ADT and DFT messages, carrying the guarantor’s demographics, employer information, and relationship to the patient. The guarantor may be the patient themselves, a spouse, parent, or other responsible party.
GT1 Field Reference
Section titled “GT1 Field Reference”| Seq | Name | Type | Opt | Description |
|---|---|---|---|---|
GT1-1 | Set ID | SI | R | Sequence number (usually 1) |
★ GT1-2 | Guarantor Number | CX | O | Guarantor account identifier |
★ GT1-3 | Guarantor Name | XPN | R | Full name of guarantor |
| When GT1-11=SELF, this matches PID-5 (Patient Name). For other relationships, the guarantor is a different person. | ||||
GT1-4 | Guarantor Spouse Name | XPN | O | Spouse name |
★ GT1-5 | Guarantor Address | XAD | O | Mailing address |
| Used for patient statement mailing. If empty, billing systems typically fall back to PID-11 (Patient Address). | ||||
★ GT1-6 | Guarantor Phone (Home) | XTN | O | Home phone number |
GT1-7 | Guarantor Phone (Business) | XTN | O | Work phone number |
★ GT1-8 | Guarantor Date of Birth | TS | O | DOB for identity verification |
GT1-9 | Guarantor Administrative Sex | IS | O | M, F, O, U |
GT1-10 | Guarantor Type | IS | O | Individual, organization |
★ GT1-11 | Guarantor Relationship | CE | O | SELF, SPO, PAR, GRD, OTH |
| SELF=Patient is guarantor, SPO=Spouse, PAR=Parent (pediatric), GRD=Guardian, CHD=Adult child (elderly patient). | ||||
GT1-12 | Guarantor SSN | ST | O | Social Security Number |
GT1-13 | Guarantor Date Begin | DT | O | Start of financial responsibility |
| Important for pediatric patients (changes at age 18), divorce settlements, and long-term care (Medicaid eligibility). | ||||
GT1-14 | Guarantor Date End | DT | O | End of financial responsibility |
GT1-15 | Guarantor Priority | NM | O | Priority order (1 = primary) |
| GT1-15=1 is primary guarantor (statements and collections go here first). Secondary guarantors contacted if primary cannot pay. | ||||
★ GT1-16 | Guarantor Employer Name | XPN | O | Employer name |
GT1-17 | Guarantor Employer Address | XAD | O | Employer address |
GT1-18 | Guarantor Employer Phone | XTN | O | Employer phone |
GT1-19 | Guarantor Employee ID | CX | O | Employee ID number |
GT1-20 | Guarantor Employment Status | IS | O | Employed, retired, student, etc. |
GT1-21 | Guarantor Organization Name | XON | O | Organization name (if GT1-10 = organization) |
★ GT1-3 R Full name of guarantor
When GT1-11=SELF, this matches PID-5 (Patient Name). For other relationships, the guarantor is a different person.
★ GT1-5 O Mailing address
Used for patient statement mailing. If empty, billing systems typically fall back to PID-11 (Patient Address).
★ GT1-11 O SELF, SPO, PAR, GRD, OTH
SELF=Patient is guarantor, SPO=Spouse, PAR=Parent (pediatric), GRD=Guardian, CHD=Adult child (elderly patient).
GT1-13 O Start of financial responsibility
Important for pediatric patients (changes at age 18), divorce settlements, and long-term care (Medicaid eligibility).
GT1-15 O Priority order (1 = primary)
GT1-15=1 is primary guarantor (statements and collections go here first). Secondary guarantors contacted if primary cannot pay.
R = Required, O = Optional, C = Conditional, W = Withdrawn (backward compatibility only)
GT1-11: Guarantor Relationship Codes
Section titled “GT1-11: Guarantor Relationship Codes”| Code | Relationship | Description |
|---|---|---|
| SELF | Self | Patient is their own guarantor |
| SPO | Spouse | Spouse is financially responsible |
| PAR | Parent | Parent responsible (pediatric patients) |
| GRD | Guardian | Legal guardian |
| CHD | Child | Adult child responsible for elderly patient |
| OTH | Other | Other responsible party |
When GT1-11 = SELF, GT1-3 (Guarantor Name) matches PID-5 (Patient Name). For other relationships, the guarantor is a different person from the patient.
GT1 vs NK1
Section titled “GT1 vs NK1”GT1 and NK1 both carry associated person information but serve different purposes:
| Feature | GT1 (Guarantor) | NK1 (Next of Kin) |
|---|---|---|
| Purpose | Financial — who pays the bill | Clinical — who to contact |
| Used by | Billing/revenue cycle systems | Clinical/nursing systems |
| Required for | Account creation, statement mailing | Emergency notifications, care decisions |
| Same person? | Often, but not always | May overlap with GT1 |
A spouse may appear as both GT1 (responsible for payment) and NK1 (emergency contact), but each segment routes to different downstream systems.
Key Implementation Considerations
Section titled “Key Implementation Considerations”Multiple Guarantors
Section titled “Multiple Guarantors”Patients may have more than one guarantor (e.g., divorced parents sharing financial responsibility). GT1-15 (Priority) determines the primary guarantor:
- GT1-15 = 1: Primary guarantor — statements and collection efforts go here first
- GT1-15 = 2+: Secondary guarantors — contacted if primary cannot pay
Financial Responsibility Dates
Section titled “Financial Responsibility Dates”GT1-13 (Date Begin) and GT1-14 (Date End) define the guarantor’s period of responsibility. This is important for:
- Pediatric patients: Guarantor changes when child turns 18
- Divorce settlements: Responsibility may transfer between parents
- Long-term care: Guarantor may change when Medicaid eligibility begins
Statement Mailing
Section titled “Statement Mailing”Billing systems use GT1-5 (Address) for patient statement mailing. If GT1-5 is empty, systems typically fall back to PID-11 (Patient Address). Accurate guarantor addresses reduce returned mail and improve collections.