Registrants

Create and update registrants with complete curl request examples.

Release timing: This page includes changes planned for 9 October 2026. See the deployment note before using the updated operations or inputs.

Build a request

Example data only. No request is sent.

POST

Choose the destination IDsOrganization IDEvent ID

Start with these fields

external_id

External identifier.

external_email

Invited identity email.

external_first_name

Invited first name.

external_last_name

Invited last name.

send_email

Defaults to true. Use a JSON boolean, not the string "false".

Add optional fields (14)

Include external_company

Invited company.

Include external_title

Invited title.

Include pitch

Networking pitch.

Include skip_networking

Networking preference.

Include appearance

dark, light, or system.

Include ticket_type_list_id

Invalid or omitted POST values fall back to the event's default ticket type.

Include custom_list_ids

Full custom-list membership replacement. [] removes all custom-list memberships.

Include persona

Name, not ID. Brella imports or resolves the event value.

Include function

Name, not ID.

Include industry

Name, not ID.

Include selected_interests

Entries use interest_id and intent_ids. PATCH replaces unselected interests.

Include custom_fields_attributes

Entries use key plus value or values.

Include seats

Requested seat count. Default to 1 \- Do NOT use values larger than 1\. Seats are a legacy concept that is to be deprecated.

Include external_qr_string

External QR override, at most 255 characters and unique within the event. Null or blank clears the record override. Internal Brella QR formats, including encoded variants, are rejected. A joined registrant may then inherit a personal invite value; read external-qr-string for the effective value and internal-qr-string for the stable Brella value.

Use the API address and token from your environment. Set up authentication.

curl --fail-with-body --silent --show-error --globoff --max-time 30 --request POST \
  --url "${BRELLA_API_BASE_URL}"'/api/core/organizations/123/events/456/registrants' \
  --header "Accept: application/vnd.brella.v4+json" \
  --header "Brella-API-Access-Token: ${BRELLA_API_ACCESS_TOKEN}" \
  --header "Content-Type: application/json" \
  --data-raw '{
  "external_id": "CRM-10042",
  "external_email": "alex@example.com",
  "external_first_name": "Alex",
  "external_last_name": "Morgan",
  "send_email": false
}'

201 CreatedIllustrative response

Write-response fields

{
  "data": {
    "id": "1201",
    "type": "registrant"
  }
}

The token scope determines returned fields. This selector illustrates that configuration; it does not change your token or the request.

Collection path: events/{event_id}/registrants

POST creates an invited registrant. PATCH uses Brella’s invited-registrant update flow and can be rejected when the record’s current state is not compatible with that flow.

POST a registrant

View the complete cURL example

curl --fail-with-body --silent --show-error --globoff --max-time 30 --request POST \
  --url "${BRELLA_API_BASE_URL}"'/api/core/organizations/123/events/456/registrants' \
  --header "Accept: application/vnd.brella.v4+json" \
  --header "Brella-API-Access-Token: ${BRELLA_API_ACCESS_TOKEN}" \
  --header "Content-Type: application/json" \
  --data-raw '{
  "external_id": "CRM-10042",
  "external_email": "alex@example.com",
  "external_first_name": "Alex",
  "external_last_name": "Morgan",
  "external_company": "Example Ltd",
  "external_title": "VP Partnerships",
  "pitch": "Looking for distribution partners",
  "skip_networking": false,
  "ticket_type_list_id": 301,
  "custom_list_ids": [
    401,
    402
  ],
  "persona": "Buyer",
  "function": "Partnerships",
  "industry": "Technology",
  "selected_interests": [
    {
      "interest_id": 701,
      "intent_ids": [
        801,
        802
      ]
    }
  ],
  "custom_fields_attributes": [
    {
      "key": "company_size",
      "values": [
        "51-200"
      ]
    }
  ],
  "seats": 1,
  "send_email": false,
  "external_qr_string": "BADGE-10042"
}'

The response type is registrant. Useful write-response fields include external_id, external_email, external_first_name, external_last_name, ticket_type_list_id, seats_count, and updated_at.

PATCH a registrant

This example updates profile source data and fully replaces custom-list membership and interest selections.

View the complete cURL example

curl --fail-with-body --silent --show-error --globoff --max-time 30 --request PATCH \
  --url "${BRELLA_API_BASE_URL}"'/api/core/organizations/123/events/456/registrants/1201' \
  --header "Accept: application/vnd.brella.v4+json" \
  --header "Brella-API-Access-Token: ${BRELLA_API_ACCESS_TOKEN}" \
  --header "Content-Type: application/json" \
  --data-raw '{
  "external_title": "SVP Partnerships",
  "pitch": "Expanding our partner network",
  "custom_list_ids": [
    401,
    403
  ],
  "selected_interests": [
    {
      "interest_id": 701,
      "intent_ids": [
        801
      ]
    }
  ],
  "send_email": false
}'

Set or clear an external QR value

Allow the external_qr_string input mapping in the registrant scope. POST can set it on a new invited registrant; PATCH can set an override on an invited or joined registrant:

{ "external_qr_string": "BADGE-10042" }

Clear the target record’s override with:

{ "external_qr_string": null }

Blank strings also clear it. Non-blank values must be unique within the event, at most 255 characters and outside Brella’s internal QR format. Internal-format and duplicate values return validation errors.

Configure external_qr_string and internal_qr_string as readable or write-response fields only when needed. external-qr-string returns the effective value; a joined registrant can inherit a claimed personal invite’s value after its own override is cleared. internal-qr-string remains the stable Brella QR value. Check both to verify the intended scanning result; QR behavior explains the fallback.

Input reference

19 inputs. Expand a field for its request type and update behavior. These are the example request keys; your administrator can configure aliases.

external_idScalar string or `null`

POST: Optional
PATCH: Optional

External identifier.

external_emailScalar string or `null`

POST: Optional
PATCH: Optional

Invited identity email.

external_first_nameScalar string or `null`

POST: Optional
PATCH: Optional

Invited first name.

external_last_nameScalar string or `null`

POST: Optional
PATCH: Optional

Invited last name.

external_companyScalar string or `null`

POST: Optional
PATCH: Optional

Invited company.

external_titleScalar string or `null`

POST: Optional
PATCH: Optional

Invited title.

pitchScalar string or `null`

POST: Optional
PATCH: Optional

Networking pitch.

skip_networkingJSON boolean

POST: Optional
PATCH: Optional

Networking preference.

appearanceScalar string or `null`

POST: Optional
PATCH: Optional

dark, light, or system.

ticket_type_list_idScalar ID

POST: Optional
PATCH: Optional

Invalid or omitted POST values fall back to the event's default ticket type.

custom_list_idsArray of scalar IDs

POST: Optional
PATCH: Optional

Full custom-list membership replacement. [] removes all custom-list memberships.

personaScalar string or `null`

POST: Optional
PATCH: Optional

Name, not ID. Brella imports or resolves the event value.

functionScalar string or `null`

POST: Optional
PATCH: Optional

Name, not ID.

industryScalar string or `null`

POST: Optional
PATCH: Optional

Name, not ID.

selected_interestsArray of objects

POST: Optional
PATCH: Optional

Entries use interest_id and intent_ids. PATCH replaces unselected interests.

custom_fields_attributesArray of objects

POST: Optional
PATCH: Optional

Entries use key plus value or values.

seatsScalar number

POST: Optional
PATCH: Optional

Requested seat count. Default to 1 \- Do NOT use values larger than 1\. Seats are a legacy concept that is to be deprecated.

send_emailJSON boolean

POST: Optional
PATCH: Optional

Defaults to true. Use a JSON boolean, not the string "false".

external_qr_stringScalar string or `null`

POST: Optional
PATCH: Optional, including joined registrants

Understand collection updates

What does this PATCH change?

Compare omitted, replaced and cleared collections. These are conceptual field values, not a live API response.

CollectionRequest behavior

Before

{
  "custom_list_ids": [
    401,
    402
  ]
}

PATCH body

{}

After

{
  "custom_list_ids": [
    401,
    402
  ]
}

Omitting the field keeps the existing collection.

List IDs must belong to the event. This illustrates a valid, authorized update.