Offramps

Prerequisite: You need a KYC-approved wallet with tokens and an active bank account on your organization. See KYC Overview for what verification requires, and KYC WebSDK for the hosted flow.

Redemptions are independent of how much was onramped. A customer can sell (redeem) any amount of a stablebond up to their current balance — it does not need to match the amount they originally bought. There’s no paired buy/sell or lot tracking; partial redemptions and redeeming tokens acquired elsewhere both work.

Offramp Flow

Discover Assets

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Either of these endpoints will give you the asset identifiers needed for quotes:

GET /ramp/assets — Requires auth. Returns all rampable stablecoins and stablebonds for the specified blockchain. The currency parameter controls sort priority (matching assets appear first). Best for building integrations where you already know the customer’s wallet.
GET /lookup/stablebonds — Public, no auth. Returns all stablebonds across all chains with pricing and supply data. Best for exploring what’s available before onboarding a customer.

Use the identifier from either response as the asset value in your quote.

Asset identifier format differs by chain:

Solana — Base58 mint address (e.g. AvvetPGuuB5FD5m86fpw3LtDKyQoUFT1mG9WarNQLW4q)
Stellar — CODE:ISSUER format (e.g. CETES:GC3CW7...)
EVM (Base, Polygon) — Raw contract address only (e.g. 0xcC77c598d42f2f78Beb42C91d12B9d4041a5cE29)

Using SYMBOL:0x... on EVM chains will return UnsupportedBlockchain.

Create a Quote — POST /ramp/quote

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All orders require a quote. Quotes expire after 2 minutes. For offramps, set type: "offramp" with the token identifier as sourceAsset and the fiat currency as targetAsset. See POST /ramp/quote for the full schema.

curl -X POST https://api.sand.etherfuse.com/ramp/quote \
  -H "Authorization: <api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "quoteId": "<uuid>",        # You generate this UUID
    "customerId": "<org_uuid>",  # From onboarding
    "blockchain": "base",
    "quoteAssets": {
      "type": "offramp",
      "sourceAsset": "0xcC77c598d42f2f78Beb42C91d12B9d4041a5cE29",
      "targetAsset": "MXN"
    },
    "sourceAmount": "50"
  }'

curl -X POST https://api.etherfuse.com/ramp/quote \
  -H "Authorization: <api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "quoteId": "<uuid>",        # You generate this UUID
    "customerId": "<org_uuid>",  # From onboarding
    "blockchain": "base",
    "quoteAssets": {
      "type": "offramp",
      "sourceAsset": "0x834df4C1d8f51Be24322E39e4766697BE015512F",
      "targetAsset": "MXN"
    },
    "sourceAmount": "50"
  }'

Partner fees: If your organization has a partner fee configured, it is applied automatically. To override per-quote, add "partnerFeeBps": 100 (0–500) to the request body. See Partner Fees for details.

Create an Order — POST /ramp/order

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The quoteId carries the direction, blockchain, and amounts from your quote — no need to repeat them. The response includes orderId and a burnTransaction — a pre-built, unsigned transaction that burns the customer’s tokens. See POST /ramp/order for the full schema.

Do not build your own transaction unless using anchor mode. Always use the burnTransaction provided by Etherfuse — it contains the correct parameters, amounts, and contract calls.

EVM offramps need a token approval first. On Base/Polygon/Monad, the token must be approve()-d before this call via POST /ramp/evm/approve — otherwise the offramp transaction fails on-chain. With gasless offramps enabled, the user doesn’t need native gas. See Base → Offramps. Stellar offramps instead require the wallet to already hold XLM and the asset’s trustline, or no burnTransaction is produced — see Stellar.

curl -X POST https://api.sand.etherfuse.com/ramp/order \
  -H "Authorization: <api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "orderId": "<uuid>",              # You generate this UUID
    "bankAccountId": "<bank_account_uuid>", # From onboarding
    "cryptoWalletId": "<wallet_uuid>",   # From onboarding
    "quoteId": "<quote_id_from_step_1>"  # From Step 2
  }'

curl -X POST https://api.etherfuse.com/ramp/order \
  -H "Authorization: <api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "orderId": "<uuid>",              # You generate this UUID
    "bankAccountId": "<bank_account_uuid>", # From onboarding
    "cryptoWalletId": "<wallet_uuid>",   # From onboarding
    "quoteId": "<quote_id_from_step_1>"  # From Step 2
  }'

The response includes a statusPage URL — e.g. https://sandbox.etherfuse.com/ramp/order/<order_uuid>. Open it in a browser to sign the burn transaction and track progress without building wallet integration into your test harness.

Optional order fields: memo attaches your own reference string to the order. feePayer applies only to Stellar contract-wallet (C-address) offramps — a contract wallet can’t be the transaction source, so you provide a funded Stellar G-account public key to pay the network fee.

Sign the Burn Transaction

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Embedded wallets skip this step. If the order’s wallet is an embedded wallet, there is no burnTransaction to sign. Wait for approval on the order (via webhook, WebSocket, or polling) and submit the owner’s signature to POST /ramp/order/{orderId}/approvals instead.

Unlike onramps, offramps require an on-chain action: the customer must sign and submit the burn transaction to release their tokens. You can handle this two ways:

In your app — Deserialize the burnTransaction from the order response or order_updated webhook, sign it with the customer’s wallet, and broadcast it to the network.
Via the status page — Use the statusPage URL from the order response (e.g. https://sandbox.etherfuse.com/ramp/order/<order_uuid>) to review and sign the transaction in the Etherfuse UI.

Stellar transactions expire in ~1–2 minutes. If the customer takes too long, submitting the burn tx returns tx_too_late. Don’t reuse the stale one — call POST /ramp/order/{order_id}/regenerate_tx (a fresh burnTransaction arrives over the order_updated webhook). Polling it ~once a minute keeps a signable tx in front of the user. See Stellar.

Verify Completion — GET /ramp/order/{order_uuid}

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Once the burn is confirmed on-chain, the system detects it and initiates the fiat payout automatically. Status progression: created → funded (burn confirmed) → completed (fiat sent) → finalized (reversal window passed). See GET /ramp/order for the full response schema.

No fiat simulation needed. Unlike onramps, there is no fiat_received step for offramps. The sandbox processes the fiat payout automatically once the burn transaction is confirmed on-chain.

curl -H "Authorization: <api_key>" \
  https://api.sand.etherfuse.com/ramp/order/<order_uuid>

curl -H "Authorization: <api_key>" \
  https://api.etherfuse.com/ramp/order/<order_uuid>

Anchor Mode (Stellar Only)

For Stellar offramps, you can use anchor mode instead of the default burn transaction flow. In anchor mode, you build and submit the payment transaction yourself — Etherfuse provides the destination address and memo. This is useful when you want full control over transaction construction, or when integrating with wallets that support SEP-24-style withdrawal flows.

Create Order with useAnchor

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Add "useAnchor": true to your order request. The quote must be for a Stellar offramp.

curl -X POST https://api.sand.etherfuse.com/ramp/order \
  -H "Authorization: <api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "orderId": "<uuid>",
    "bankAccountId": "<bank_account_uuid>",
    "cryptoWalletId": "<wallet_uuid>",
    "quoteId": "<quote_id>",
    "useAnchor": true
  }'

curl -X POST https://api.etherfuse.com/ramp/order \
  -H "Authorization: <api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "orderId": "<uuid>",
    "bankAccountId": "<bank_account_uuid>",
    "cryptoWalletId": "<wallet_uuid>",
    "quoteId": "<quote_id>",
    "useAnchor": true
  }'

The response includes anchor-specific fields instead of a burnTransaction:

{
  "offramp": {
    "orderId": "...",
    "withdrawAnchorAccount": "GABPM7AXX...",
    "withdrawMemo": "RkFLRU1FTU8xMjM0NTY3ODkw...",
    "withdrawMemoType": "hash"
  }
}

Build and Submit Payment

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Build a Stellar payment transaction to the withdrawAnchorAccount with:

Asset & amount from your quote (e.g., USDC, XLM, or CETES)
Memo — decode withdrawMemo from base64, then attach as a Memo.hash

const memoBytes = Buffer.from(withdrawMemo, "base64");
const tx = new StellarSdk.TransactionBuilder(sourceAccount, { fee, networkPassphrase })
  .addOperation(StellarSdk.Operation.payment({
    destination: withdrawAnchorAccount,
    asset: sendAsset,
    amount: quoteAmount,
  }))
  .addMemo(StellarSdk.Memo.hash(memoBytes.toString("hex")))
  .setTimeout(300)
  .build();

Sign and submit the transaction to the Stellar network.

Track Order Status

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The rest of the flow is identical to standard offramps. Once the payment is detected on-chain, the order progresses through created → funded → completed → finalized.

Payments sent without a memo or with an unrecognized memo will be automatically refunded to the sender address.

Show Chain-specific quote examples

Solana — Use the Base58 mint address as sourceAsset:

{
  "blockchain": "solana",
  "quoteAssets": {
    "type": "offramp",
    "sourceAsset": "AvvetPGuuB5FD5m86fpw3LtDKyQoUFT1mG9WarNQLW4q",
    "targetAsset": "MXN"
  }
}

Stellar — Use CODE:ISSUER format:

{
  "blockchain": "stellar",
  "quoteAssets": {
    "type": "offramp",
    "sourceAsset": "CETES:GC3CW7...",
    "targetAsset": "MXN"
  }
}

Base / Polygon — Use the raw contract address:

{
  "blockchain": "base",
  "quoteAssets": {
    "type": "offramp",
    "sourceAsset": "0xcC77c598d42f2f78Beb42C91d12B9d4041a5cE29",
    "targetAsset": "MXN"
  }
}

Show Common errors

Error	Cause	Fix
`UnsupportedBlockchain`	Using `SYMBOL:0x...` format on an EVM chain	Use the raw contract address only
`Terms and conditions have not been completed`	Wallet not KYC-approved	Complete the onboarding flow
`Quote not found or expired`	Quote TTL is 2 minutes	Create a fresh quote
`Bank account not found`	Bank account not owned by the requesting org	Verify the bank account belongs to your organization
`quote_id is required`	Missing quote — the quoteless path is deprecated	Create a quote via `POST /ramp/quote` first
No `burnTransaction` / no webhook (Stellar)	Wallet isn’t funded with XLM or is missing the asset’s trustline, so the tx can’t be built	Fund the wallet (~1.5 XLM) and add the trustline first. See Stellar
`tx_too_late` (Stellar)	Burn transaction expired (~1–2 min) before submission	Regenerate via `regenerate_tx` and resubmit promptly
`OrderTooSmall` (EVM)	Offramp too small to cover the bundled gas fee (fee can’t exceed 50% of the order)	Offramp a larger amount (≳ 50 CETES). See Base

Get Started

Concepts

User Authentication

Integration Guides

KYC

Blockchains

Resources

Offramp Flow

Anchor Mode (Stellar Only)

​Offramp Flow

​Anchor Mode (Stellar Only)

Offramp Flow

Anchor Mode (Stellar Only)