X12 834 benefit enrollment: format and example

834 structure

The full X12 834 layout from its OpenEDI definition, the same model ediFabric uses to parse, validate and generate it: 21 loops and 76 segment positions, in file order. Loops are shaded and their segments indented; Max use is how many times a segment or loop may repeat.

Segment / loop	Name	Usage	Max use
`ST`	Transaction Set Header	Required	1
`BGN`	Beginning Segment	Required	1
`REF`	Transaction Set Policy Number	Situational	1
`DTP`	File Effective Date	Situational	>1
`QTY`	Transaction Set Control Totals	Situational	3
Any order	The loops below can appear in any order	Required	1
Loop 1000A	Sponsor Name	Required	1
`N1`	Sponsor Name	Required	1
Loop 1000B	Payer	Required	1
`N1`	Payer	Required	1
Loop 1000C	TPA Broker Name	Situational	2
`N1`	TPA Broker Name	Required	1
Loop 1100C	TPA Broker Account Information	Situational	1
`ACT`	TPA Broker Account Information	Required	1
Loop 2000	Member Level Detail	Required	>1
`INS`	Member Level Detail	Required	1
Any order	The loops below can appear in any order	Required	1
`REF`	Subscriber Identifier	Required	1
`REF`	Member Policy Number	Situational	1
`REF`	Member Supplemental Identifier	Situational	13
`DTP`	Member Level Dates	Situational	24
Any order	The loops below can appear in any order	Required	1
Loop 2100A	Member Name	Required	1
`NM1`	Member Name	Required	1
`PER`	Member Communications Numbers	Situational	1
`N3`	Member Residence Street Address	Situational	1
`N4`	Member City State ZIP Code	Situational	1
`DMG`	Member Demographics	Situational	1
`EC`	Employment Class	Situational	>1
`ICM`	Member Income	Situational	1
`AMT`	Member Policy Amounts	Situational	7
`HLH`	Member Health Information	Situational	1
`LUI`	Member Language	Situational	>1
Loop 2100B	Incorrect Member Name	Situational	1
`NM1`	Incorrect Member Name	Required	1
`DMG`	Incorrect Member Demographics	Situational	1
Loop 2100C	Member Mailing Address	Situational	1
`NM1`	Member Mailing Address	Required	1
`N3`	Member Mail Street Address	Required	1
`N4`	Member Mail City State ZIP Code	Required	1
Loop 2100D	Member Employer	Situational	3
`NM1`	Member Employer	Required	1
`PER`	Member Employer Communications Numbers	Situational	1
`N3`	Member Employer Street Address	Situational	1
`N4`	Member Employer City State ZIP Code	Situational	1
Loop 2100E	Member School	Situational	3
`NM1`	Member School	Required	1
`PER`	Member School Commmunications Numbers	Situational	1
`N3`	Member School Street Address	Situational	1
`N4`	Member School City State ZIP Code	Situational	1
Loop 2100F	Custodial Parent	Situational	1
`NM1`	Custodial Parent	Required	1
`PER`	Custodial Parent Communications Numbers	Situational	1
`N3`	Custodial Parent Street Address	Situational	1
`N4`	Custodial Parent City State ZIP Code	Situational	1
Loop 2100G	Responsible Person	Situational	13
`NM1`	Responsible Person	Required	1
`PER`	Responsible Person Communications Numbers	Situational	1
`N3`	Responsible Person Street Address	Situational	1
`N4`	Responsible Person City State ZIP Code	Situational	1
Loop 2100H	Drop Off Location	Situational	1
`NM1`	Drop Off Location	Required	1
`N3`	Drop Off Location Street Address	Situational	1
`N4`	Drop Off Location City State ZIP Code	Situational	1
Loop 2200	Disability Information	Situational	>1
`DSB`	Disability Information	Required	1
`DTP`	Disability Eligibility Dates	Situational	2
Loop 2300	Health Coverage	Situational	99
`HD`	Health Coverage	Required	1
`DTP`	Health Coverage Dates	Required	6
`AMT`	Health Coverage Policy	Situational	9
Any order	The loops below can appear in any order	Situational	1
`REF`	Health Coverage Policy Number	Situational	14
`REF`	Prior Coverage Months	Situational	1
`IDC`	Identification Card	Situational	3
Loop 2310	Provider Information	Situational	30
`LX`	Provider Information	Required	1
`NM1`	Provider Name	Required	1
`N3`	Provider Address	Situational	2
`N4`	Provider City State ZIP Code	Situational	1
`PER`	Provider Communications Numbers	Situational	2
`PLA`	Provider Change Reason	Situational	1
Loop 2320	Coordinationof Benefits	Situational	5
`COB`	Coordinationof Benefits	Required	1
`REF`	Additional Coordinationof Benefits Identifiers	Situational	4
`DTP`	Coordinationof Benefits Eligibility Dates	Situational	2
Loop 2330	Coordinationof Benefits Related Entity	Situational	3
`NM1`	Coordinationof Benefits Related Entity	Required	1
`N3`	Coordinationof Benefits Related Entity Address	Situational	1
`N4`	Coordinationof Benefits Other Insurance Company City State ZIP Code	Situational	1
`PER`	Administrative Communications Contact	Situational	1
Loop LS	Additional Reporting Categories	Situational	1
`LS`	Additional Reporting Categories	Required	1
Loop 2700	Member Reporting Categories	Situational	>1
`LX`	Member Reporting Categories	Required	1
Loop 2750	Reporting Category	Situational	1
`N1`	Reporting Category	Required	1
`REF`	Reporting Category Reference	Situational	1
`DTP`	Reporting Category Date	Situational	1
`LE`	Additional Reporting Categories Termination	Required	1
`SE`	Transaction Set Trailer	Required	1

Usage follows the 005010X220A1 implementation guide: Required segments must be sent, Situational ones only when the guide's condition applies. Trading partners often add their own rules in companion guides - ediFabric templates can be adjusted to match. Open the element-level definition in the EdiNation spec library.

Sample 834 file

An enrollment for one subscriber with health coverage details. Paste it into EdiNation to see every element named and validated.

ISA*00*          *00*          *ZZ*386028429      *30*382328142      *050221*0602*U*00501*000012345*0*P*:~
GS*BE*386028429*382328142*20050221*0602*000012345*X*005010X220A1~
ST*834*12345*005010X220A1~
BGN*00*12456*19980520*1200****2~
N1*P5**FI*999888777~
N1*IN**FI*654456654~
INS*Y*18*021*20*A***FT~
REF*0F*123456789~
REF*1L*123456001~
DTP*356*D8*19960523~
NM1*IL*1*DOE*JOHN*P***34*123456789~
PER*IP**HP*7172343334*WP*7172341240~
N3*100 MARKET ST*APT 3G~
N4*CAMP HILL*PA*17011**CY*CUMBERLAND~
DMG*D8*19400816*M~
HD*021**HLT~
DTP*348*D8*19960601~
COB*P*890111*5~
HD*021**DEN~
DTP*348*D8*19960601~
HD*021**VIS~
DTP*348*D8*19960601~
SE*21*12345~
GE*1*000012345~
IEA*1*000012345~

The same 834 as JSON

ediFabric turns every loop, segment and element into a named field. This is the transaction from the sample, in the JSON that ediFabric Native and Cloud return and accept.

{
  "ST": {
    "TransactionSetIdentifierCode_01": "834",
    "TransactionSetControlNumber_02": "12345",
    "ImplementationConventionPreference_03": "005010X220A1"
  },
  "BGN_BeginningSegment": {
    "TransactionSetPurposeCode_01": "00",
    "TransactionSetReferenceNumber_02": "12456",
    "TransactionSetCreationDate_03": "19980520",
    "TransactionSetCreationTime_04": "1200",
    "ActionCode_08": "2"
  },
  "AllN1": {
    "Loop1000A": {
      "N1_SponsorName": {
        "EntityIdentifierCode_01": "P5",
        "IdentificationCodeQualifier_03": "FI",
        "IntermediaryBankIdentifier_04": "999888777"
      }
    },
    "Loop1000B": {
      "N1_Payer": {
        "EntityIdentifierCode_01": "IN",
        "IdentificationCodeQualifier_03": "FI",
        "IntermediaryBankIdentifier_04": "654456654"
      }
    }
  },
  "Loop2000": [
    {
      "INS_MemberLevelDetail": {
        "InsuredIndicator_01": "Y",
        "IndividualRelationshipCode_02": "18",
        "MaintenanceTypeCode_03": "021",
        "MaintenanceReasonCode_04": "20",
        "BenefitStatusCode_05": "A",
        "EmploymentStatusCode_08": "FT"
      },
      "AllREF": {
        "REF_SubscriberIdentifier": {
          "ReferenceIdentificationQualifier_01": "0F",
          "MemberGrouporPolicyNumber_02": "123456789"
        },
        "REF_MemberPolicyNumber": {
          "ReferenceIdentificationQualifier_01": "1L",
          "MemberGrouporPolicyNumber_02": "123456001"
        }
      },
      "DTP_MemberLevelDates": [
        {
          "DateTimeQualifier_01": "356",
          "DateTimePeriodFormatQualifier_02": "D8",
          "DateTimePeriod_03": "19960523"
        }
      ],
      "AllNM1": {
        "Loop2100A": {
          "NM1_MemberName": {
            "EntityIdentifierCode_01": "IL",
            "EntityTypeQualifier_02": "1",
            "ResponseContactLastorOrganizationName_03": "DOE",
            "ResponseContactFirstName_04": "JOHN",
            "ResponseContactMiddleName_05": "P",
            "IdentificationCodeQualifier_08": "34",
            "ResponseContactIdentifier_09": "123456789"
          },
          "PER_MemberCommunicationsNumbers": {
            "ContactFunctionCode_01": "IP",
            "CommunicationNumberQualifier_03": "HP",
            "ResponseContactCommunicationNumber_04": "7172343334",
            "CommunicationNumberQualifier_05": "WP",
            "ResponseContactCommunicationNumber_06": "7172341240"
          },
          "N3_MemberResidenceStreetAddress": {
            "ResponseContactAddressLine_01": "100 MARKET ST",
            "ResponseContactAddressLine_02": "APT 3G"
          },
          "N4_MemberCity_State_ZIPCode": {
            "AdditionalPatientInformationContactCityName_01": "CAMP HILL",
            "AdditionalPatientInformationContactStateCode_02": "PA",
            "AdditionalPatientInformationContactPostalZoneorZIPCode_03": "17011",
            "LocationQualifier_05": "CY",
            "LocationIdentifier_06": "CUMBERLAND"
          },
          "DMG_MemberDemographics": {
            "DateTimePeriodFormatQualifier_01": "D8",
            "DependentBirthDate_02": "19400816",
            "DependentGenderCode_03": "M"
          }
        }
      },
      "Loop2300": [
        {
          "HD_HealthCoverage": {
            "MaintenanceTypeCode_01": "021",
            "InsuranceLineCode_03": "HLT"
          },
          "DTP_HealthCoverageDates": [
            {
              "DateTimeQualifier_01": "348",
              "DateTimePeriodFormatQualifier_02": "D8",
              "DateTimePeriod_03": "19960601"
            }
          ],
          "Loop2320": [
            {
              "COB_CoordinationofBenefits": {
                "PayerResponsibilitySequenceNumberCode_01": "P",
                "MemberGrouporPolicyNumber_02": "890111",
                "CoordinationofBenefitsCode_03": "5"
              }
            }
          ]
        },
        {
          "HD_HealthCoverage": {
            "MaintenanceTypeCode_01": "021",
            "InsuranceLineCode_03": "DEN"
          },
          "DTP_HealthCoverageDates": [
            {
              "DateTimeQualifier_01": "348",
              "DateTimePeriodFormatQualifier_02": "D8",
              "DateTimePeriod_03": "19960601"
            }
          ]
        },
        {
          "HD_HealthCoverage": {
            "MaintenanceTypeCode_01": "021",
            "InsuranceLineCode_03": "VIS"
          },
          "DTP_HealthCoverageDates": [
            {
              "DateTimeQualifier_01": "348",
              "DateTimePeriodFormatQualifier_02": "D8",
              "DateTimePeriod_03": "19960601"
            }
          ]
        }
      ]
    }
  ],
  "SE": {
    "NumberofIncludedSegments_01": "21",
    "TransactionSetControlNumber_02": "12345"
  }
}

Parse and validate an 834 file

Read the file into typed objects with ediFabric .NET, convert it to JSON in process with the ediFabric Native bindings for Python, Java and C, or post it to the ediFabric Cloud REST API from any language.

.NET
Python
Java
C
Cloud

using EdiFabric.Templates.Hipaa5010;

License.SetSerial("YOUR_SERIAL_KEY");

using (var stream = File.OpenRead(@"C:\edi\BenefitEnrollment.txt"))
using (var reader = new X12Reader(stream, "EdiFabric.Templates.Hipaa"))
{
    var items = await reader.ReadToEndAsync();
    foreach (var transaction in items.OfType<TS834>())
    {
        if (transaction.IsValid(out MessageErrorContext errors))
            Console.WriteLine($"{transaction.ST.TransactionSetControlNumber_02} is valid");
        else
            Console.WriteLine(string.Join(Environment.NewLine, errors.Flatten()));
    }
} Install and get started 834 example project Walkthrough
import json
import edifabric_x12 as ef

serial = "YOUR_SERIAL_KEY"
ef.load_library()
ef.set_serial(serial)
ef.set_map(json.dumps({"default": serial, "maps": {}}))

edi = open("BenefitEnrollment.txt", "rb").read()
output, offset = ef.parse(edi, ef.ParseMode.JSON_VALIDATE)
transactions = output[:offset]
report = json.loads(output[offset:])
print(report["errors_count"]) Python bindingsediFabric Native
import com.edifabric.nativex12.EdiFabricX12;
import com.edifabric.nativex12.ParseMode;
import com.edifabric.nativex12.ParseResult;

String serial = "YOUR_SERIAL_KEY";
EdiFabricX12.loadLibrary();
EdiFabricX12.setSerial(serial);
EdiFabricX12.setMap("{\"default\":\"" + serial + "\",\"maps\":{}}");

String edi = Files.readString(Path.of("BenefitEnrollment.txt"));
ParseResult result = EdiFabricX12.parse(edi, ParseMode.JSON_VALIDATE);
System.out.println(result.getTransactions());
System.out.println(result.getReport()); Java bindingsediFabric Native
#include "edifabric_x12.h"

const char *serial = "YOUR_SERIAL_KEY";
ef_parse_result result;

if (ef_load_library(NULL) != 0)
    return 1;
ef_set_serial(serial);
ef_set_map("{\"default\":\"YOUR_SERIAL_KEY\",\"maps\":{}}");

char *edi = read_file("BenefitEnrollment.txt", NULL);   /* helper in example_all_functions.c */
if (ef_parse(edi, EF_PARSE_JSON_VALIDATE, NULL, &result) == 0) {
    /* transactions = output[0 .. offset), report = output[offset .. length) */
    fwrite(result.output.data, 1, (size_t)result.output.length, stdout);
    ef_free(result.output.data);
} C bindingsediFabric Native
curl -X POST 'https://api.edination.com/v2/x12/read' \
-H 'Ocp-Apim-Subscription-Key: YOUR_SERIAL_KEY' \
-H 'Content-Type: application/octet-stream' \
--data-binary '@BenefitEnrollment.txt' TranslateValidateediFabric Cloud

Generate an 834 file

Populate a TS834 object in .NET, or pass JSON in the shape shown above to ediFabric Native or ediFabric Cloud, and get a valid 834 file back.

.NET
Python
Java
C
Cloud

using EdiFabric.Templates.Hipaa5010;

License.SetSerial("YOUR_SERIAL_KEY");

var transaction = new TS834();

//  Used to indicate the start of a transaction set and to specify a transaction set control number.
transaction.ST = new ST();
transaction.ST.TransactionSetIdentifierCode_01 = "834";
transaction.ST.TransactionSetControlNumber_02 = "0001";

//  This is an original transaction uniquely identified by the sender with reference #12456. The transaction was created on 5/20/1998 at 12:00 Noon.
transaction.BGN_BeginningSegment = new BGN_BeginningSegment();
transaction.BGN_BeginningSegment.TransactionSetPurposeCode_01 = "00";
transaction.BGN_BeginningSegment.TransactionSetReferenceNumber_02 = "12456";
transaction.BGN_BeginningSegment.TransactionSetCreationDate_03 = "19980520";
transaction.BGN_BeginningSegment.TransactionSetCreationTime_04 = "1200";
transaction.BGN_BeginningSegment.ActionCode_08 = "2";

//  Occurrence of N1 Loops in any order
transaction.AllN1 = new All_N1_834();

//  Begin 1000A Loop
transaction.AllN1.Loop1000A = new Loop_1000A_834();

// ... set the remaining loops and segments the same way

// SegmentBuilders is in the Common project of the example repository
using (var stream = new MemoryStream())
{
    using (var writer = new X12Writer(stream))
    {
        writer.Write(SegmentBuilders.BuildIsa("1"));
        writer.Write(SegmentBuilders.BuildGs("1", "SENDER1", "RECEIVER1", "005010X220A1"));
        writer.Write(transaction);
    }
    Console.WriteLine(Encoding.UTF8.GetString(stream.ToArray()));
} Install and get started Full 834 build methodExample repository
import json
import edifabric_x12 as ef

serial = "YOUR_SERIAL_KEY"
ef.load_library()
ef.set_serial(serial)
ef.set_map(json.dumps({"default": serial, "maps": {}}))

# the transactions JSON returned by ef.parse, edited or produced by your application
transactions = open("BenefitEnrollment.json", "rb").read()
edi = ef.build(transactions, postfix="\r\n")
print(edi) Python bindings
import com.edifabric.nativex12.EdiFabricX12;

String serial = "YOUR_SERIAL_KEY";
EdiFabricX12.loadLibrary();
EdiFabricX12.setSerial(serial);
EdiFabricX12.setMap("{\"default\":\"" + serial + "\",\"maps\":{}}");

// the transactions JSON returned by parse, edited or produced by your application
String transactions = Files.readString(Path.of("BenefitEnrollment.json"));
String edi = EdiFabricX12.build(transactions, "\r\n");
System.out.println(edi); Java bindings
#include "edifabric_x12.h"

ef_buffer edi;

if (ef_load_library(NULL) != 0)
    return 1;
ef_set_serial("YOUR_SERIAL_KEY");
ef_set_map("{\"default\":\"YOUR_SERIAL_KEY\",\"maps\":{}}");

/* the transactions JSON returned by ef_parse, edited or produced by your application */
char *transactions = read_file("BenefitEnrollment.json", NULL);
if (ef_build(transactions, "\r\n", &edi) == 0) {
    fwrite(edi.data, 1, (size_t)edi.length, stdout);
    ef_free(edi.data);
} C bindings
# the JSON returned by /read, edited or produced by your application
curl -X POST 'https://api.edination.com/v2/x12/write' \
-H 'Ocp-Apim-Subscription-Key: YOUR_SERIAL_KEY' \
-H 'Content-Type: application/json' \
--data-binary '@BenefitEnrollment.json' \
-o 'BenefitEnrollment.txt' How-tosediFabric Cloud

834 questions

What is the difference between a full and a change 834 file?

BGN08 tells the receiver how to apply the file. 2 means change (update) and carries only additions, changes and terminations. 4 means verify, and RX means replace - the file is the complete membership.

How is a member added, changed or terminated?

INS03 carries the maintenance type code: 021 addition, 001 change, 024 cancellation or termination, 030 audit or compare. INS04 gives the reason.

Does the plan send a business response to an 834?

HIPAA only defines the 999 acknowledgment. Many plans return discrepancy reports or their own 834 audit files by trading partner agreement.

How do I parse and generate X12 834 files in .NET, Python, Java and C?

In .NET, install EdiFabric and EdiFabric.Templates.Hipaa, read the file with X12Reader into TS834 objects and write them back with X12Writer. From Python, Java or C, use ediFabric Native, which converts 834 files to JSON and JSON back to X12 inside your process. From any other language, post the file to the ediFabric Cloud REST API.

Related transactions

X12 820 - Payroll Deducted and Other Group Premium Payment
X12 270 - Eligibility, Coverage or Benefit Inquiry
X12 271 - Eligibility, Coverage or Benefit Information
All EDI transactions →

X12 834 Benefit Enrollment and Maintenance

At a glance