Lendfy API

A REST API for the whole loan book — the same API the Lendfy app runs on. Use it to bring customers in from another system, keep an external product in sync, or build your own tooling on top of your data.

Overview

The base URL for all requests:

https://api.lendfy.io/v1

Every request and response body is JSON (Content-Type: application/json). All traffic requires TLS. Responses include an X-Request-Id header — quote it when reporting an issue and we can find the exact request in our logs.

Authentication

Authenticate with your organization's API key as a Bearer token. Keys start with lfy_ and are scoped to your organization — you can only ever see your own data.

curl https://api.lendfy.io/v1/customers \
  -H "Authorization: Bearer lfy_your_api_key"

Errors

Errors use one envelope everywhere — a machine-readable code, a human-readable message, and the request id for correlation. Some errors attach extra fields (for example existing_id on a duplicate conflict).

{
  "error": {
    "code": "duplicate_suspected",
    "message": "This looks like Maria Lopez, who is already on file…",
    "request_id": "req_8f31c2",
    "existing_id": "7b0c…"
  }
}

Idempotency

Every write (POST, PATCH) requires an Idempotency-Key header — any unique string, a UUID is perfect. If a request is retried with the same key and body, the stored response is replayed instead of the work running twice (the replay carries X-Idempotent-Replay: true). The same key with a different body returns 409 idempotency_conflict.

# a network timeout is safe to retry with the same key —
# the customer can never be created twice
curl -X POST https://api.lendfy.io/v1/customers \
  -H "Authorization: Bearer lfy_…" \
  -H "Idempotency-Key: 6f9c1a2e-4b7d-4c11-9a3f-2f8e5d6c7b01" \
  -H "Content-Type: application/json" \
  -d '{"first_name":"Maria","last_name":"Lopez"}'

Pagination

List endpoints are cursor-paginated. Pass limit (default 25, max 100); the response carries next_cursor — pass it back as cursor for the next page. A null cursor means you've reached the end.

{ "data": [ … ], "next_cursor": "MTcyNT…" }

Money, dates & PII

• Money is integer cents. 25500 means $255.00 — no floats, ever.
• Dates are YYYY-MM-DD; timestamps are ISO-8601 UTC. Day-boundary math (due dates, days past due) runs in your organization's timezone.
• Sensitive numbers go in but never come out. You may send a full SSN and full bank account number; Lendfy stores and returns only the last four of each (SSNs additionally keep a salted one-way hash used for duplicate matching). Phone numbers normalize to digits.

List & search customers

Newest first. query matches name and email (case-insensitive contains), a 7+ digit string matches phone, and a 4-digit string matches SSN last-four.

Retrieve a customer

{
  "id": "7b0c1d2e-…",
  "first_name": "Maria",
  "last_name": "Lopez",
  "email": "maria@example.com",
  "phone": "8185550142",
  "dob": "1990-04-12",
  "ssn_last4": "6789",
  "payroll_cadence": "biweekly",
  "bank_routing": "021000021",
  "bank_account_last4": "6789",
  "store_id": "1111…",
  "status": "active",
  "external_source": null,
  "external_ref": null,
  "created_at": "2026-08-10T20:14:03Z",
  "…": "address, employment, ID and consent fields omitted for brevity"
}

Create a customer

Only first_name and last_name are required; everything else is optional and validated when present. Key fields:

Duplicate protection

If the SSN — or name plus date of birth — matches a customer already on file, the create returns 409 duplicate_suspected with existing_id and existing_name so you can link to the existing record instead. If it really is a different person, re-send with "allow_duplicate": true.

Update a customer

Partial update: only the fields present in the body change. An explicit null clears an optional field; names cannot be emptied. Sending a new ssn or bank_account replaces the stored last-four (the full numbers are still never stored). Every update is audited with before-and-after values.

Importing a book from another system

Bringing customers over from a previous LMS? Stamp each record with your identifiers so the two systems stay linkable:

• external_source — a short name for the system of origin (e.g. "legacy_lms").
• external_ref — that system's customer id. The pair is unique per organization, so re-imports can't double-create.

Combine with Idempotency-Key per record and the duplicate protection above, and an import script that crashes halfway is safe to simply run again.

List loans

Loan rows carry principal, due date, the balance and days-past-due as most recently reported, and any scheduled collection (collection_scheduled_date / _method).

Retrieve a loan

Loan ledger

The loan's money history — disbursements, payments, adjustments — newest first, with the running balance. Amounts follow the cents convention: payments are negative, charges positive.

Other endpoints

The surface keeps growing with the product. Also available today:

• GET /v1/servicing/summary — the whole book's KPIs in one call.
• GET /v1/collections/queue — past-due accounts bucketed by days late, with promise and schedule state.
• GET /v1/customers/{id}/timeline — notes, promises, and observed payments merged into one feed.
• POST /v1/customers/{id}/notes and POST /v1/promises — collections activity.
• POST /v1/loans · /fund · /payments · /cancel · /void — origination and payments for Lendfy-native loans.
• GET/POST /v1/customers/{id}/cards — debit cards on file (brand + last-4 + expiry only; the PAN is never stored).
• GET/POST /v1/loans/{id}/documents (+ /{doc_id}/download) — the loan file: signed agreements, receipts, disclosures. Upload is base64 JSON (kind, filename, content_type, data_b64, 10 MB cap); removal is soft, so a loan file never silently loses a contract.
• GET/POST /v1/loans/{id}/notes — the loan's own notes thread (also visible on the customer's timeline).
• GET/POST /v1/customers/{id}/references — personal references (relative/friend/coworker contact records; DELETE to remove).
• GET/POST /v1/customers/{id}/calls — the call log. Append-only: direction, outcome, phone, note.
• GET/POST /v1/customers/{id}/communications — sent emails/texts/letters, one history per customer. Append-only; log sends from external tools here.
• GET/POST /v1/customers/{id}/documents (+ /{doc_id}/download) — customer-level uploads (IDs, statements); the listing also includes every loan-file document, labeled by loan.
• GET/POST /v1/customers/{id}/bank-accounts · /employers · /phones — multiple on file, exactly one primary each (POST …/{item_id}/primary to switch; the primary mirrors onto the customer's flat fields). Account numbers: last-4 only.
• POST /v1/loans/{id}/schedule-payment (+ list/cancel) — ACH from the primary account or a card on file; stamps the loan's scheduled-collection fields.
• GET/POST /v1/loans/{id}/payment-plan (+ /cancel) — the agreed installment split; must sum to the balance, one active plan per loan.
• GET /v1/integrations · PUT/DELETE /v1/integrations/dropbox-sign (+ /test) — bring your own vendor keys. Keys are write-only: reads return a masked form.
• POST /v1/loans/{id}/esign/send · GET /v1/loans/{id}/esign (+ /refresh, /cancel) — send a pending loan's agreement for e-signature through Dropbox Sign; the signed PDF files into the loan documents as esign_receipt. Webhook: POST /v1/webhooks/dropbox-sign.
• GET/PUT /v1/settings — tenant configuration. pay_frequencies controls the label and availability of each payroll cadence everywhere (keys are fixed; payday math depends on them).
• GET/POST /v1/api-keys (+ DELETE /{id}) — API key management. The secret is returned once at creation; revocation is immediate, and the key authenticating the request cannot revoke itself.
• POST /v1/stores/{id}/zone — assign a store to a zone (region grouping); zones ride the store objects.
• GET /v1/exports/customers.csv · loans.csv · collections.csv — full-book CSV exports.