Write off a loan

POST/api/v1/loans/{instrument_id}/write-off

Write off all (default) or part of a loan's balance.

Request Body:

principal_cents: Principal to write off (optional; omit for the full remaining balance).
write_off_date: Effective date (optional, defaults to today).
memo: Optional journal-entry memo.

Effect:

Loans we made post to Bad Debt Expense; debt we owe posts to Debt Forgiveness Income.
A full write-off also clears accrued unpaid interest and marks the loan written_off.

Operation ID: write_off_loan·View as markdown·OpenAPI slice

Authentication

Bearer token authentication. Pass your DayZero API token in the Authorization header and the target business UUID in x-business-id.

Parameters

Path

instrument_idstringrequired

Request body

Schema: LoanWriteOffRequest

write_off_datestring · date
principal_centsinteger: Principal to write off; omit for the full remaining balance.
memostring

Responses

201Successful Response

Schema: SuccessEnvelope_LoanWriteOffResponse_

successboolean
messagestring
codestring
dataLoanWriteOffResponse

400Bad Request - Invalid input

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

401Unauthorized - Missing/invalid token or no access to this business

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

403Forbidden - Insufficient permissions

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

404Not Found - Resource does not exist

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

409Conflict - Resource already exists or is in an incompatible state

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

422Validation Error

Schema: ErrorResponse

errorstringrequired: Error category: validation_error, unauthorized, forbidden, not_found, conflict, rate_limited, server_error, or service_unavailable.
messagestringrequired: Human-readable explanation, safe to show to end users.
codestringrequired: Stable machine-readable code in CATEGORY_NNN form (e.g. NOT_FOUND_006, AUTH_010, GEN_002).
request_idstring: Correlation id for support requests. Echoes the x-request-id request header when one was supplied.
errorsobject: Field-level validation messages keyed by field name. Present on 400/422 validation failures only.

Code samples

POST/api/v1/loans/{instrument_id}/write-off

bash

curl -X POST 'https://api.ondayzero.com/api/v1/loans/{instrument_id}/write-off' \
  -H 'Authorization: Bearer dz_your_token' \
  -H 'x-business-id: YOUR_BUSINESS_ID' \
  -H 'Content-Type: application/json' \
  -d '{
  "write_off_date": "2026-01-01",
  "principal_cents": 0,
  "memo": "string"
}'