Direct Withdrawals

This guide walks you through withdrawing from an Amplify vault by calling the WithdrawQueue smart contract directly. It covers every contract method you need to call, in order, including fee calculation, share conversion, and order status polling.

How Withdrawals Work

Unlike deposits, withdrawals are not instant. They use a queue-based model:

Approve vault shares

Grant the WithdrawQueue permission to transfer your vault shares by calling approve() on the BoringVault (share token) contract.

Submit a withdrawal order

Call submitOrder() on the WithdrawQueue. Your shares are locked and a withdrawal order is created.

Vault operator fulfills the order

The vault operator processes the queue (typically within 24 hours) and transfers the want asset (e.g., USDC) to your receiver address.

Why can’t I withdraw instantly? Vault assets may be deployed in DeFi strategies. The vault operator needs time to unwind positions and source liquidity. This is standard across DeFi vault protocols.

What You’ll Need

Requirement	Description
Contract addresses	`boringVaultAddress`, `withdrawQueueAddress`, and `accountantAddress` — see Vault Discovery
ABI	Provided below
RPC endpoint	An Ethereum node URL
Private key or wallet	To sign and send transactions
Vault shares	You must have shares from a prior deposit

ABI Reference

WithdrawQueue ABI

[
  {
    "inputs": [
      {
        "components": [
          { "name": "amountOffer", "type": "uint256" },
          { "name": "wantAsset", "type": "address" },
          { "name": "intendedDepositor", "type": "address" },
          { "name": "receiver", "type": "address" },
          { "name": "refundReceiver", "type": "address" },
          {
            "components": [
              { "name": "approvalMethod", "type": "uint8" },
              { "name": "approvalV", "type": "uint8" },
              { "name": "approvalR", "type": "bytes32" },
              { "name": "approvalS", "type": "bytes32" },
              { "name": "submitWithSignature", "type": "bool" },
              { "name": "deadline", "type": "uint256" },
              { "name": "eip2612Signature", "type": "bytes" }
            ],
            "name": "signatureParams",
            "type": "tuple"
          }
        ],
        "name": "params",
        "type": "tuple"
      }
    ],
    "name": "submitOrder",
    "outputs": [{ "name": "orderIndex", "type": "uint256" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [{ "name": "orderIndex", "type": "uint256" }],
    "name": "getOrderStatus",
    "outputs": [{ "name": "", "type": "uint8" }],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "minimumOrderSize",
    "outputs": [{ "name": "", "type": "uint256" }],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "feeModule",
    "outputs": [{ "name": "", "type": "address" }],
    "stateMutability": "view",
    "type": "function"
  }
]

FeeModule ABI

[
  {
    "inputs": [
      { "name": "amount", "type": "uint256" },
      { "name": "offerAsset", "type": "address" },
      { "name": "wantAsset", "type": "address" },
      { "name": "receiver", "type": "address" }
    ],
    "name": "calculateOfferFees",
    "outputs": [{ "name": "feeAmount", "type": "uint256" }],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [],
    "name": "offerFeePercentage",
    "outputs": [{ "name": "", "type": "uint256" }],
    "stateMutability": "view",
    "type": "function"
  }
]

[
  {
    "inputs": [
      { "name": "spender", "type": "address" },
      { "name": "amount", "type": "uint256" }
    ],
    "name": "approve",
    "outputs": [{ "name": "", "type": "bool" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      { "name": "owner", "type": "address" },
      { "name": "spender", "type": "address" }
    ],
    "name": "allowance",
    "outputs": [{ "name": "", "type": "uint256" }],
    "stateMutability": "view",
    "type": "function"
  },
  {
    "inputs": [{ "name": "account", "type": "address" }],
    "name": "balanceOf",
    "outputs": [{ "name": "", "type": "uint256" }],
    "stateMutability": "view",
    "type": "function"
  }
]

[
  {
    "inputs": [],
    "name": "getRateInQuoteSafe",
    "outputs": [{ "name": "rate", "type": "uint256" }],
    "stateMutability": "view",
    "type": "function"
  }
]

Contract Method Reference

`submitOrder(params)`

Field	Type	Description
`amountOffer`	`uint256`	Vault shares to offer. Shares have 18 decimals, so `1000000000000000000` = 1 share.
`wantAsset`	`address`	Token you want to receive (e.g., USDC address)
`intendedDepositor`	`address`	Must match the caller (`msg.sender`)
`receiver`	`address`	Where the want asset is sent when fulfilled
`refundReceiver`	`address`	Where vault shares are returned if the order is cancelled
`signatureParams`	`tuple`	For standard ERC-20 approval flow, pass all zeros (see below)

Empty Signature Params

When you’ve already called approve(), pass empty signature params to indicate standard ERC-20 approval:

Field	Value
`approvalMethod`	`0` (EIP20_APPROVE)
`approvalV`	`0`
`approvalR`	`0x` + 32 zero bytes
`approvalS`	`0x` + 32 zero bytes
`submitWithSignature`	`false`
`deadline`	`0`
`eip2612Signature`	`0x` (empty bytes)

Order Statuses

Value	Status	Meaning
`0`	NOT_FOUND	Order doesn’t exist
`1`	PENDING	Waiting for the vault operator to fulfill
`2`	COMPLETE	Fulfilled — want asset sent to receiver
`3`	COMPLETE_PRE_FILLED	Filled during submission
`4`	PENDING_REFUND	Being refunded
`5`	COMPLETE_REFUNDED	Cancelled — shares returned
`6`	FAILED_TRANSFER_REFUNDED	Transfer failed — shares returned

Withdrawal Fees

The WithdrawQueue charges a fee on withdrawal orders via its FeeModule. You should check the fee before submitting to display accurate amounts to your users. The fee is deducted from your amountOffer in vault shares — meaning you receive the want asset equivalent of amountOffer - feeAmount.

How to read the fee

This requires two contract reads: Step 1 — Get the FeeModule address from the WithdrawQueue:

WithdrawQueue.feeModule() → address feeModuleAddress

Step 2 — Calculate the fee for your specific withdrawal:

FeeModule.calculateOfferFees(
  amount,      // vault share amount (uint256)
  offerAsset,  // BoringVault address (the share token)
  wantAsset,   // token you want to receive (e.g., USDC)
  receiver     // address receiving the want asset
) → uint256 feeAmount

The feeAmount is in vault shares (18 decimals). To get the fee percentage:

FeeModule.offerFeePercentage() → uint256 feePercentage

The returned value uses 18-decimal precision (e.g., 5000000000000000 = 0.5%).

The fee is subtracted from the vault shares you offer. If you offer 100 shares and the fee is 0.5 shares, only 99.5 shares worth of the want asset will be sent to the receiver. Account for this when displaying withdrawal amounts to users.

Converting Withdrawal Amount to Shares

Users typically think in terms of the want asset (e.g., “I want to withdraw 1,000 USDC”), but amountOffer is denominated in vault shares. Use the Accountant’s exchange rate to convert.

Contract call

Accountant.getRateInQuoteSafe() → uint256 rate

rate represents the amount of the want asset per 1e18 vault shares.

Conversion formula

To withdraw a specific amount of the want asset:

sharesNeeded = (wantAmount × 1e18) / rate

For example, to withdraw 1,000 USDC (6 decimals):

wantAmount   = 1000 × 1e6 = 1000000000
sharesNeeded = (1000000000 × 1e18) / rate

Don’t forget to account for withdrawal fees when calculating the share amount. If there’s a 0.5% fee, you’ll need to offer slightly more shares: sharesNeeded / (1 - feePercentage).

Minimum Order Size

Each WithdrawQueue enforces a minimum order size. Check it before submitting:

WithdrawQueue.minimumOrderSize() → uint256 minimumShares

If your amountOffer is below this threshold, the transaction will revert with AmountBelowMinimum.

Withdrawal Walkthrough

Check your share balance (read)

Confirm you hold enough vault shares to withdraw.

BoringVault.balanceOf(yourAddress) → uint256 shareBalance

Convert want amount to shares (read)

If you know the want asset amount, convert it to shares.

Accountant.getRateInQuoteSafe() → uint256 rate

Then calculate: sharesNeeded = (wantAmount × 1e18) / rateIf you already know the share amount you want to offer, skip this step.

Check the withdrawal fee (read)

Get the FeeModule address and calculate the fee that will be deducted.

WithdrawQueue.feeModule() → address feeModuleAddress

FeeModule.calculateOfferFees(
  sharesNeeded,          // from Step 2
  boringVaultAddress,    // the share token (offer asset)
  wantAssetAddress,      // e.g., USDC
  receiverAddress        // where want asset goes
) → uint256 feeAmount

The net shares applied to the withdrawal = sharesNeeded - feeAmount. Display this to the user so they know the effective withdrawal amount.

Check the minimum order size (read)

Ensure your order meets the minimum.

WithdrawQueue.minimumOrderSize() → uint256 minimumShares

If sharesNeeded < minimumShares, the order will be rejected.

Check existing allowance (read)

See if the WithdrawQueue already has permission to transfer your shares.

BoringVault.allowance(yourAddress, withdrawQueueAddress) → uint256

If the returned value is ≥ your sharesNeeded, skip to Step 7.

Approve vault shares to the WithdrawQueue (transaction)

Grant the WithdrawQueue permission to transfer your vault shares.

BoringVault.approve(withdrawQueueAddress, sharesNeeded) → bool

Wait for the transaction to be mined before proceeding.

Submit the withdrawal order (transaction)

Call submitOrder() on the WithdrawQueue with empty signature params (since you used ERC-20 approval in Step 6).

WithdrawQueue.submitOrder({
  amountOffer:       sharesNeeded,
  wantAsset:         wantAssetAddress,      // e.g., USDC
  intendedDepositor: yourAddress,            // must be msg.sender
  receiver:          receiverAddress,        // where want asset goes
  refundReceiver:    yourAddress,            // where shares go if cancelled
  signatureParams: {
    approvalMethod:      0,
    approvalV:           0,
    approvalR:           bytes32(0),
    approvalS:           bytes32(0),
    submitWithSignature: false,
    deadline:            0,
    eip2612Signature:    0x
  }
}) → uint256 orderIndex

The return value orderIndex uniquely identifies your order. Save it to check status or cancel later.You can also extract orderIndex from the OrderSubmitted event in the transaction receipt logs.

Poll for order completion (read)

The vault operator typically fulfills orders within 24 hours. Check the status:

WithdrawQueue.getOrderStatus(orderIndex) → uint8 status

Poll periodically (e.g., every 60 seconds) until status ≥ 2:

2 (COMPLETE) — Want asset has been sent to your receiver address
5 (COMPLETE_REFUNDED) — Order was cancelled, shares returned
6 (FAILED_TRANSFER_REFUNDED) — Transfer failed, shares returned

Example values (withdrawing ~1,000 USDC worth of shares on Ethereum mainnet)

Parameter	Value
`amountOffer`	Calculated from exchange rate (e.g., `990099009900...`)
`wantAsset`	`0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48` (USDC)
`intendedDepositor`	Your wallet address
`receiver`	Your wallet address
`refundReceiver`	Your wallet address
`signatureParams`	All zeros (see empty signature params table above)

Troubleshooting

AmountBelowMinimum

Your amountOffer is below the queue’s minimum order size. Call minimumOrderSize() to check the threshold, and increase your amount.

InvalidDepositor

The intendedDepositor field doesn’t match the transaction sender. Set it to the wallet address that’s sending the transaction.

AssetNotSupported

The wantAsset address isn’t enabled for this vault. Query the vault config to find supported withdrawal assets.

PermitFailedAndAllowanceTooLow

Vault shares haven’t been approved to the WithdrawQueue. Call BoringVault.approve() first.

TellerIsPaused

Vault operations are temporarily paused by the operator. Wait and retry later. You can check programmatically with Teller.isPaused() — see Pause State.

Next Steps

Direct Cancellations — Cancel a pending withdrawal order
Vault Queries & Monitoring — Read withdrawal fees, check pause state, monitor withdrawal history
Direct Deposits — Deposit tokens into a vault
SDK Withdrawals Guide — Use the Amplify SDK instead

Getting started

Origin - Branded Stablecoins

Amplify - Stablecoin Earn

Access - Borrow

USDG0

How Withdrawals Work

What You’ll Need

ABI Reference

WithdrawQueue ABI

FeeModule ABI

Contract Method Reference

`submitOrder(params)`

Empty Signature Params

Order Statuses

Withdrawal Fees

How to read the fee

Converting Withdrawal Amount to Shares

Contract call

Conversion formula

Minimum Order Size

Withdrawal Walkthrough

Example values (withdrawing ~1,000 USDC worth of shares on Ethereum mainnet)

Troubleshooting

Next Steps

​How Withdrawals Work

​What You’ll Need

​ABI Reference

​WithdrawQueue ABI

​FeeModule ABI

​BoringVault ABI (ERC-20 for share approval)

​Accountant ABI (for share conversion)

​Contract Method Reference

​submitOrder(params)

​Empty Signature Params

​Order Statuses

​Withdrawal Fees

​How to read the fee

​Converting Withdrawal Amount to Shares

​Contract call

​Conversion formula

​Minimum Order Size

​Withdrawal Walkthrough

​Example values (withdrawing ~1,000 USDC worth of shares on Ethereum mainnet)

​Troubleshooting

​Next Steps

How Withdrawals Work

What You’ll Need

ABI Reference

WithdrawQueue ABI

FeeModule ABI

BoringVault ABI (ERC-20 for share approval)

Accountant ABI (for share conversion)

Contract Method Reference

`submitOrder(params)`

Empty Signature Params

Order Statuses

Withdrawal Fees

How to read the fee

Converting Withdrawal Amount to Shares

Contract call

Conversion formula

Minimum Order Size

Withdrawal Walkthrough

Example values (withdrawing ~1,000 USDC worth of shares on Ethereum mainnet)

Troubleshooting

Next Steps