> ## Documentation Index > Fetch the complete documentation index at: https://docs.hel.io/llms.txt > Use this file to discover all available pages before exploring further. # Prepare a Withdrawal > Quotes a withdrawal and returns a lane-specific payload for the holder to sign. No authentication required (rate-limited). **Note:** When using the production environment at [moonpay.hel.io](http://app.hel.io), set your API endpoint to `api.hel.io/v1`. For the development environment, use `api.dev.hel.io/v1`. Display `summary` as your confirmation screen. The quote and `token` expire at `summary.expiresAt`. `sourceCurrencyId` is always required. Optionally pass `customerId` (max 255 characters) to attach a merchant-defined end-user identifier to the quote. Inspect `prepared.kind` to determine what to sign: `raw` (Solana `unsignedTx`), `userop` (EVM ERC-4337 user operation), or `hypercore` (Hyperliquid EIP-712 `typedData`). ## OpenAPI ````yaml POST /v1/withdraw/{withdrawalConfigId}/prepare openapi: 3.0.0 info: title: Helio Open API description: |- API schema and definitions for Helio API.
The API is using two types of Authentication, for dashboard endpoints we use JSON Web Token (JWT) that is generated by self custodial wallet signing a message from API.
We also support authentication with API Key and Secret which can be generated on Helio dashboard. version: 1.0.0 contact: {} servers: - description: Helio API (Mainnet) url: https://api.hel.io - description: Helio API (Devnet) url: https://api.dev.hel.io security: [] tags: - name: Webhooks - name: Exports - name: Currencies description: >- Supported currencies endpoint, includes fiat and digital assets
Authentication: None externalDocs: description: Helio product documentation url: https://docs.hel.io/ paths: /v1/withdraw/{withdrawalConfigId}/prepare: post: tags: - Withdrawals summary: Prepare a Withdrawal description: >- Quotes a withdrawal and returns a lane-specific payload for the holder to sign. No authentication required (rate-limited). `sourceCurrencyId` is required. operationId: WithdrawalPrepareController_prepare parameters: - name: withdrawalConfigId in: path required: true description: The withdrawal config ID. schema: type: string requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/PreparedWithdrawalDto' responses: '200': description: Withdrawal prepared successfully. content: application/json: schema: $ref: '#/components/schemas/PreparedWithdrawalEntity' '400': description: >- Validation error (invalid addresses, amount below minimum, no route available). '404': description: Withdrawal config not found. security: [] components: schemas: PreparedWithdrawalDto: type: object required: - ownerAddress - recipient - amount - toCurrencyId - sourceCurrencyId properties: ownerAddress: type: string description: >- Holder's source wallet address. Format is lane-specific (e.g. Solana base58 for Solana `raw`, EVM checksummed address for EVM `raw`/`hyperliquid`). recipient: type: string description: Destination address on any supported chain. amount: type: string pattern: ^\d+$ description: >- Amount in atomic units as a decimal-free string (e.g. `1500000` for 1.5 USDC). toCurrencyId: type: string description: Destination currency Mongo ID. sourceCurrencyId: type: string description: Source currency Mongo ID from the withdrawal config. customerId: type: string maxLength: 255 description: >- Optional merchant identifier for the end user (max 255 characters). Persisted on prepare and echoed on the withdrawal detail and webhooks. Not applied on re-quote. PreparedWithdrawalEntity: type: object properties: withdrawalDetailId: type: string description: Per-request ID. Use for submit and status polling. token: type: string description: JWT quote token. Pass verbatim on submit. prepared: $ref: '#/components/schemas/PreparedTransaction' summary: $ref: '#/components/schemas/PreparedWithdrawalSummary' PreparedTransaction: oneOf: - $ref: '#/components/schemas/RawPreparedTransaction' - $ref: '#/components/schemas/UserOpPreparedTransaction' - $ref: '#/components/schemas/HypercorePreparedTransaction' discriminator: propertyName: kind mapping: raw: $ref: '#/components/schemas/RawPreparedTransaction' userop: $ref: '#/components/schemas/UserOpPreparedTransaction' hypercore: $ref: '#/components/schemas/HypercorePreparedTransaction' PreparedWithdrawalSummary: type: object properties: sourceToken: type: string sourceAmount: type: string destinationToken: type: string destinationAmount: type: string description: Firm expected output net of fees. destinationAmountMin: type: string description: Minimum output after slippage. maxSlippageBps: type: number description: Maximum slippage tolerance in basis points. estimatedPriceImpact: type: number description: Estimated price impact, when available. bridgeFee: $ref: '#/components/schemas/WithdrawalQuoteFee' applicationFee: $ref: '#/components/schemas/WithdrawalQuoteFee' protocolFee: $ref: '#/components/schemas/WithdrawalQuoteFee' totalFee: $ref: '#/components/schemas/WithdrawalQuoteFee' expiresAt: type: string format: date-time description: Quote expiry. Re-quote before this passes. RawPreparedTransaction: type: object required: - kind - chain - unsignedTx properties: kind: type: string enum: - raw chain: type: string description: Blockchain symbol (e.g. `SOL`). unsignedTx: type: string description: >- Base64-encoded unsigned VersionedTransaction, already sponsor-signed as fee payer. UserOpPreparedTransaction: type: object required: - kind - chain - userOp - entryPoint properties: kind: type: string enum: - userop chain: type: string description: EVM blockchain symbol (e.g. `BASE`). userOp: type: object additionalProperties: true description: Unsigned ERC-4337 UserOperation. Shape depends on the 4337 version. entryPoint: type: string description: EntryPoint contract address for the user operation. authorization: type: object properties: chainId: type: string address: type: string nonce: type: string description: Optional EIP-7702 authorization metadata. HypercorePreparedTransaction: type: object required: - kind - chain - typedData properties: kind: type: string enum: - hypercore chain: type: string description: Blockchain symbol for the HyperCore action. typedData: $ref: '#/components/schemas/PreparedWithdrawalTypedData' description: EIP-712 typed data for the holder to sign. WithdrawalQuoteFee: type: object properties: amount: type: string description: Fee amount in atomic units of `currency`. currency: allOf: - $ref: '#/components/schemas/Currency' nullable: true description: Matched fee currency, or null when unresolved. PreparedWithdrawalTypedData: type: object properties: domain: $ref: '#/components/schemas/PreparedWithdrawalTypedDataDomain' types: type: object additionalProperties: type: array items: $ref: '#/components/schemas/PreparedWithdrawalTypedDataField' primaryType: type: string message: type: object additionalProperties: true Currency: type: object properties: blockchain: $ref: '#/components/schemas/Blockchain' id: type: string symbol: type: string name: type: string mintAddress: type: string coinMarketCapId: type: number decimals: type: number minDecimals: type: number symbolPrefix: type: string order: type: number type: enum: - FIAT - DIGITAL type: string features: type: array items: type: string enum: - PAYMENT_PRICING - PAYMENT_RECIPIENT - SWAP iconUrl: type: string required: - blockchain - id - symbol - name - mintAddress - coinMarketCapId - decimals - order PreparedWithdrawalTypedDataDomain: type: object properties: name: type: string version: type: string chainId: type: number verifyingContract: type: string PreparedWithdrawalTypedDataField: type: object properties: name: type: string type: type: string Blockchain: type: object properties: engine: $ref: '#/components/schemas/BlockchainEngine' id: type: string name: type: string symbol: type: string enum: - SOL - ETH - POLYGON - BASE - BITCOIN required: - engine - id - name - symbol BlockchainEngine: type: object properties: id: type: string type: type: string enum: - EVM - SOL - BTC required: - id - type ````