Alpaca Broker API — Funding & Transfers

Getting cash into and out of end-user accounts. There are three rails, and the model splits cleanly into bank links (persistent) and transfers (the actual money movement).

> Read alpaca-broker-integration first. Broker API + HTTP Basic auth. For moving cash between accounts in your omnibus (vs. to/from the outside world), see alpaca-broker-journals — that's a different mechanism.

Reference

• Guide: https://docs.alpaca.markets/docs/funding-accounts
• API ref: https://docs.alpaca.markets/reference/createtransferforaccount
• Live schema: alpaca-docs MCP → get-endpoint title "Broker API" path /v1/accounts/{account_id}/transfers

1. The funding model

External bank ──(relationship: a persistent link)──┐
                                                    ├──> Transfer (the money movement) ──> Account cash
ACH relationship  (rail A: ACH, US domestic)        │
Bank relationship (rail B: wire, domestic + intl)   │
Funding wallet    (rail C: v1beta, multi-currency)  ┘

• A relationship links an external bank. It moves no money and has its own status; for wires it must be APPROVED before a transfer can progress.
• A transfer references a relationship by ID and moves the money. One relationship backs many transfers.

| Rail | transfer_type | Directions | Relationship | Notes | |------|-----------------|-----------|--------------|-------| | ACH | ach | INCOMING + OUTGOING | ACH relationship (relationship_id) | US domestic; set up via Plaid processor_token (recommended) | | Wire | wire | OUTGOING only | Bank relationship (bank_id) | Domestic + international (SWIFT). Incoming wires are pushed by the sending bank and booked automatically | | Funding wallet | (separate /v1beta API) | incoming / outgoing (lowercase) | Funding-wallet recipient bank | Multi-currency, swift_wire/local_rails |

2. Endpoints

| Method | Path | Purpose | |--------|------|---------| | POST/GET/DELETE | /v1/accounts/{id}/ach_relationships[/{rel_id}] | Manage ACH bank links | | POST/GET/DELETE | /v1/accounts/{id}/recipient_banks[/{bank_id}] | Manage wire recipient banks | | POST | /v1/accounts/{id}/transfers | Create transfer (ACH deposit/withdraw, or wire withdraw) | | GET | /v1/accounts/{id}/transfers | List transfers | | DELETE | /v1/accounts/{id}/transfers/{transfer_id} | Request cancel | | POST/GET | /v1beta/accounts/{id}/funding_wallet | Create / get funding wallet | | POST/GET/DELETE | /v1beta/accounts/{id}/funding_wallet/recipient_bank | Funding-wallet recipient bank | | POST | /v1beta/accounts/{id}/funding_wallet/withdrawal | Funding-wallet withdrawal | | GET | /v1beta/accounts/{id}/funding_wallet/transfers[/{transfer_id}] | List / get wallet transfers | | GET | /v2/events/funding/status | SSE — unified funding status stream (see §6) |

> The current wire-bank endpoint is /recipient_banks (schema Bank/CreateBankRequest). The older /banks name is a legacy alias.

3. Create-transfer request (POST /v1/accounts/{id}/transfers)

Required for all: transfer_type, amount (decimal string, > 0), direction.

json
// ACH deposit
{ "transfer_type": "ach", "relationship_id": "<uuid>", "amount": "100.00", "direction": "INCOMING" }

// Wire withdrawal
{ "transfer_type": "wire", "bank_id": "<uuid>", "amount": "500.00", "direction": "OUTGOING",
  "fee_payment_method": "user", "additional_information": "..." }

• relationship_id required iff ach; bank_id required iff wire (and must be the other one's empty).
• fee_payment_method (wire): user (fee deducted from amount; warn the user in UI) or invoice (firm billed monthly). Only outgoing wire fees auto-process.
• additional_information is wire-only — sending it on a non-wire request returns 422.
• The Transfer response adds id, status, fee, requested_amount (original ask), reason, timestamps.

4. Wire recipient bank (POST /v1/accounts/{id}/recipient_banks)

Required: name, bank_code, bank_code_type, account_number.

• bank_code_type: ABA (9-digit routing, domestic) or BIC (SWIFT, international).
• When BIC: country, city, state_province, postal_code, street_address become required.
• extra_fields carries intermediary/correspondent BICs (intermediary_bank1_bic…). Omitting them on international wires can cause auto-selection, delays, or extra fees — gather them up front for cross-border.
• A new bank starts QUEUED; it must reach APPROVED before a wire transfer against it progresses.

5. Transfer status state machines

Classic transfers (TransferStatus): QUEUED → APPROVAL_PENDING → PENDING → SENT_TO_CLEARING → (APPROVED) → COMPLETE, with REJECTED / CANCELED / RETURNED as failure exits.

| Terminal | Meaning | |----------|---------| | COMPLETE | Settled | | REJECTED | Rejected | | CANCELED | Client-initiated cancel | | RETURNED | Bank issued an ACH return |

(The SSE Transfer entity also reports EXPIRED, which is effectively terminal.)

Funding-wallet transfers (FundingWalletTransferStatus): PENDING, EXECUTED, COMPLETE, CANCELED, FAILED (last three terminal). Note lowercase incoming/outgoing directions here — different casing from classic transfers.

6. Events vs polling — the key reliability lesson

Classic transfers HAVE an SSE stream: GET /v2/events/funding/status. It is unified across four entity_type values — Transfer, BankRelationship, WireBank, FundingWallet — and is replayable via since/until (timestamps) or since_id/until_id (ULIDs). Use it instead of polling for classic ACH/wire status.

Funding-wallet per-transfer status appears NOT to be pushed — only wallet-level status (active/pending) is in the stream. Individual wallet transfer status (PENDING→EXECUTED→COMPLETE) must be polled via GET /v1beta/.../funding_wallet/transfers/{id}.

Lesson (hard-won): rails differ in event coverage. Decide per rail whether you consume SSE or poll, and build a status-reconciliation poller for anything not covered by events (and as a safety net even for those that are — SSE can drop). Map each Alpaca status to your own internal status with an explicit lookup table, and only poll transfers still in a non-terminal state. See alpaca-broker-reconciliation-idempotency.

> Legacy caveat: the older us/sse-events "Transfer Events" payload uses an integer event_id and lowercase statuses; the modern /v2/events/funding/status uses ULIDs. Migrate to v2.

7. Documented gotchas

• Wire fees (since 2022-06-01): outgoing domestic + international wires are charged. Reflect requested_amount vs amount+fee in your UI.
• Incoming wires need an FFC (For Further Credit) instruction to auto-book; otherwise they're handled manually.
• Travel Rule: Alpaca requires transmitter/originator info on all incoming deposits regardless of amount (below the usual FinCEN $3,000 threshold). Pass it at settlement creation; retained ≥5 years.
• ACH uses Plaid: pass the bank via processor_token. There's an instant flag on the relationship. Account types limited to CHECKING/SAVINGS.
• timing: immediate is deprecated and silently ignored (sunset 2026-08-26) — stop sending it.
• Permission errors: 403 if the account's depositable_status/withdrawable_status isn't allowed; 422 for incoming-wire attempts, missing/mismatched relationship vs bank IDs, or amounts under the (undocumented) minimums.
• Sandbox wire behavior: simulated end-to-end but asynchronous and auto-completes on weekdays only — weekend submissions don't progress until Monday. (ACH in sandbox settles instantly.)

8. The omnibus / sweep-account pattern (architecture lesson)

Many production brokers don't fund each user account by a separate external transfer. Instead:

1. Users pay you through your payment processor (or you receive a bulk wire into a firm/sweep account held at Alpaca).
2. You then journal cash from the firm account to the user's account instantly (JNLC) — no external ACH/wire per user. See alpaca-broker-journals.
3. Withdrawals reverse it: journal from user → firm account, then send one external transfer out.

This decouples your funding UX from Alpaca's transfer rails and enables "instant" deposits. It requires Alpaca review (and possibly a local money-transmitter license) — confirm with counsel. The classic transfer endpoints in this skill then handle only the firm-account-to-outside-world leg.

Related skills: internal cash movement → alpaca-broker-journals; missed-status recovery → alpaca-broker-reconciliation-idempotency; money formatting → alpaca-broker-money-precision; live status → alpaca-broker-sse-events.