Direct Deposits

This guide walks you through depositing tokens into an Amplify vault by calling the DistributorCodeDepositor smart contract directly. It covers every contract method you need to call, in order, for both the standard approval flow and the single-transaction permit flow.

How Deposits Work

When you deposit tokens (e.g., USDC) into a vault, you receive vault shares in return. These shares represent your proportional ownership of the vault’s assets and appreciate in value as the vault earns yield. There are two ways to deposit:

Flow	Transactions	Best For
Standard (Approve + Deposit)	2 transactions	All tokens, all wallets
Permit (Sign + Deposit)	1 transaction	Supported tokens only (USDC, USDG, pyUSD, USD₮0)

What You’ll Need

Requirement	Description
Contract addresses	`distributorCodeDepositorAddress` and `accountantAddress` — see Vault Discovery
ABI	Provided below — just copy into your project
RPC endpoint	An Ethereum node URL (Alchemy, Infura, QuickNode, etc.)
Private key or wallet	To sign and send transactions
Deposit tokens	The token you’re depositing (e.g., USDC) + ETH for gas

ABI Reference

You need three ABI snippets. Copy these into your project as a JSON file or inline constant.

DistributorCodeDepositor ABI

[
  {
    "inputs": [
      { "name": "depositAsset", "type": "address" },
      { "name": "depositAmount", "type": "uint256" },
      { "name": "minimumMint", "type": "uint256" },
      { "name": "to", "type": "address" },
      { "name": "distributorCode", "type": "bytes" }
    ],
    "name": "deposit",
    "outputs": [{ "name": "shares", "type": "uint256" }],
    "stateMutability": "nonpayable",
    "type": "function"
  },
  {
    "inputs": [
      { "name": "depositAsset", "type": "address" },
      { "name": "depositAmount", "type": "uint256" },
      { "name": "minimumMint", "type": "uint256" },
      { "name": "to", "type": "address" },
      { "name": "distributorCode", "type": "bytes" },
      { "name": "deadline", "type": "uint256" },
      { "name": "v", "type": "uint8" },
      { "name": "r", "type": "bytes32" },
      { "name": "s", "type": "bytes32" }
    ],
    "name": "depositWithPermit",
    "outputs": [{ "name": "shares", "type": "uint256" }],
    "stateMutability": "nonpayable",
    "type": "function"
  }
]

ERC-20 ABI (for approvals and allowance checks)

[
  {
    "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": "owner", "type": "address" }],
    "name": "nonces",
    "outputs": [{ "name": "", "type": "uint256" }],
    "stateMutability": "view",
    "type": "function"
  }
]

Accountant ABI (for slippage calculation)

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

Contract Method Reference

`deposit(depositAsset, depositAmount, minimumMint, to, distributorCode)`

Parameter	Type	Description
`depositAsset`	`address`	The ERC-20 token address to deposit (e.g., USDC: `0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48`)
`depositAmount`	`uint256`	Amount in the token’s smallest unit. USDC has 6 decimals, so `1000000` = 1 USDC.
`minimumMint`	`uint256`	Minimum shares to receive — protects against slippage. Set to `0` to accept any amount.
`to`	`address`	Address that receives the minted vault shares (usually the depositor)
`distributorCode`	`bytes`	Tracking code for referrals/attribution. Pass `0x` (empty bytes) if not applicable.

Important: depositAmount is in the token’s smallest unit. USDC has 6 decimals, so 1,000 USDC = 1000000000 (1000 × 10^6). Getting this wrong is the most common integration mistake.

`depositWithPermit(depositAsset, depositAmount, minimumMint, to, distributorCode, deadline, v, r, s)`

Same parameters as deposit(), plus:

Parameter	Type	Description
`deadline`	`uint256`	Unix timestamp after which the permit expires
`v`	`uint8`	Recovery byte of the EIP-2612 permit signature
`r`	`bytes32`	First 32 bytes of the permit signature
`s`	`bytes32`	Second 32 bytes of the permit signature

Distributor Codes

The distributorCode parameter is used for referral attribution. If Paxos Labs has provided you with a distributor code, encode it as bytes (e.g., toHex('your_code') in JavaScript, b'your_code' in Python, []byte("your_code") in Go). If you don’t have one, pass empty bytes (0x, b"", []byte{}).

Calculating `minimumMint` (Slippage Protection)

The vault’s Accountant contract publishes the exchange rate between the deposit token and vault shares. Use it to calculate a safe minimumMint.

Contract call

Accountant.getRateInQuoteSafe() → uint256 rate

rate represents the amount of the deposit asset per 1e18 vault shares (i.e., per one full share).

Calculation

expectedShares = (depositAmount × 1e18) / rate
minimumMint    = expectedShares − (expectedShares × SLIPPAGE_BPS) / 10000

Where SLIPPAGE_BPS is your slippage tolerance in basis points (e.g., 50 = 0.5%).

Setting minimumMint to 0 disables slippage protection entirely. This is fine for testing but not recommended for production — a front-running bot could manipulate the rate between your transaction submission and execution.

Standard Deposit Walkthrough

The standard flow requires two transactions: an ERC-20 approval followed by the deposit.

Check existing allowance (read)

Call the deposit token’s allowance() to see if the DistributorCodeDepositor already has sufficient spending permission.

DepositToken.allowance(yourAddress, distributorCodeDepositorAddress) → uint256

If the returned value is ≥ your depositAmount, skip to Step 3.

Approve the DistributorCodeDepositor (transaction)

Call approve() on the deposit token, granting the DistributorCodeDepositor permission to transfer your tokens.

DepositToken.approve(distributorCodeDepositorAddress, depositAmount) → bool

Wait for the transaction to be mined before proceeding.

USDT special case: USDT requires resetting the allowance to 0 before setting a new value if there’s an existing non-zero allowance. Call approve(spender, 0) first, then approve(spender, amount).

Calculate minimumMint (read)

Query the exchange rate and compute slippage protection.

Accountant.getRateInQuoteSafe() → uint256 rate

Then calculate: minimumMint = ((depositAmount × 1e18) / rate) × (10000 − SLIPPAGE_BPS) / 10000

Execute the deposit (transaction)

Call deposit() on the DistributorCodeDepositor.

DistributorCodeDepositor.deposit(
  depositAsset,      // e.g., USDC address
  depositAmount,     // e.g., 1000000000 (1,000 USDC)
  minimumMint,       // from Step 3
  to,                // recipient of vault shares (usually your address)
  distributorCode    // 0x if none
) → uint256 shares

The return value is the number of vault shares minted.

Confirm the transaction

Wait for the transaction receipt. The deposit is complete once the transaction is included in a block. You can verify by calling BoringVault.balanceOf(yourAddress) to see your new share balance.

Example values (1,000 USDC deposit on Ethereum mainnet)

Parameter	Value
`depositAsset`	`0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48`
`depositAmount`	`1000000000` (1,000 × 10^6)
`minimumMint`	Calculated from Accountant rate
`to`	Your wallet address
`distributorCode`	`0x` (empty)

Permit Deposit Walkthrough

For tokens that support EIP-2612 permits, you can combine approval and deposit into a single transaction.

Token	Permit Support
USDC	Yes
USDG	Yes
pyUSD	Yes
USD₮0	Yes
USDT	No — use standard approve + deposit

Get the permit nonce (read)

Query the token’s current nonce for your address.

DepositToken.nonces(yourAddress) → uint256 nonce

Sign the EIP-712 permit message (off-chain)

Construct and sign an EIP-712 typed data message. This is an off-chain signature — no gas required.EIP-712 Domain (varies by token — this example is for USDC on Ethereum):

Field	Value
`name`	`"USD Coin"`
`version`	`"2"`
`chainId`	`1`
`verifyingContract`	USDC token address

Permit message:

Field	Value
`owner`	Your wallet address
`spender`	`distributorCodeDepositorAddress`
`value`	`depositAmount`
`nonce`	From Step 1
`deadline`	Unix timestamp (e.g., now + 1 hour)

The EIP-712 type structure:

Permit(address owner, address spender, uint256 value, uint256 nonce, uint256 deadline)

Sign using your wallet’s signTypedData (or equivalent EIP-712 signing method). Parse the resulting signature into v, r, s components.

Calculate minimumMint (read)

Same as the standard flow:

Accountant.getRateInQuoteSafe() → uint256 rate

Execute depositWithPermit (transaction)

Call depositWithPermit() on the DistributorCodeDepositor with the permit signature.

DistributorCodeDepositor.depositWithPermit(
  depositAsset,      // e.g., USDC address
  depositAmount,     // e.g., 1000000000 (1,000 USDC)
  minimumMint,       // from Step 3
  to,                // recipient of vault shares
  distributorCode,   // 0x if none
  deadline,          // from Step 2
  v,                 // signature recovery byte
  r,                 // signature first 32 bytes
  s                  // signature second 32 bytes
) → uint256 shares

The contract verifies the permit signature on-chain, transfers your tokens, and mints vault shares — all in a single transaction.

Smart contract wallets (like Privy Smart Wallets or Safe) cannot sign permits because they don’t have a private key. Use the standard approval flow instead.

Troubleshooting

Transaction reverts with no error message

The most common cause is that minimumMint is set too high relative to the current exchange rate. Set it to 0 for testing or recalculate from the Accountant’s getRateInQuoteSafe().

PermitFailedAndAllowanceTooLow

The permit signature is invalid and there’s no existing ERC-20 approval. Double-check the permit domain parameters (name, version, verifyingContract) match the token’s EIP-712 domain. Or switch to the standard approve + deposit flow.

ERC20: insufficient allowance

You haven’t approved the DistributorCodeDepositor to spend your tokens. Call approve() on the token contract before calling deposit().

ERC20: transfer amount exceeds balance

Your wallet doesn’t hold enough of the deposit token. Check your balance before depositing.

USDT approval fails

USDT requires resetting the allowance to 0 before setting a new value if there’s an existing non-zero allowance. Call approve(spender, 0) first, then approve(spender, amount). Other tokens (USDC, USDG, pyUSD) allow overwriting an existing approval directly.

Next Steps

Direct Withdrawals — Submit a withdrawal order
Direct Cancellations — Cancel a pending withdrawal
Vault Queries & Monitoring — Read APY, TVL, check balances, and monitor withdrawal status
SDK Deposits Guide — Use the Amplify SDK instead

Getting started

Origin - Branded Stablecoins

Amplify - Stablecoin Earn

Access - Borrow

USDG0

How Deposits Work

What You’ll Need

ABI Reference

DistributorCodeDepositor ABI

ERC-20 ABI (for approvals and allowance checks)

Accountant ABI (for slippage calculation)

Contract Method Reference

`deposit(depositAsset, depositAmount, minimumMint, to, distributorCode)`

`depositWithPermit(depositAsset, depositAmount, minimumMint, to, distributorCode, deadline, v, r, s)`

Distributor Codes

Calculating `minimumMint` (Slippage Protection)

Contract call

Calculation

Standard Deposit Walkthrough

Example values (1,000 USDC deposit on Ethereum mainnet)

Permit Deposit Walkthrough

Troubleshooting

Next Steps

​How Deposits Work

​What You’ll Need

​ABI Reference

​DistributorCodeDepositor ABI

​ERC-20 ABI (for approvals and allowance checks)

​Accountant ABI (for slippage calculation)

​Contract Method Reference

​deposit(depositAsset, depositAmount, minimumMint, to, distributorCode)

​depositWithPermit(depositAsset, depositAmount, minimumMint, to, distributorCode, deadline, v, r, s)

​Distributor Codes

​Calculating minimumMint (Slippage Protection)

​Contract call

​Calculation

​Standard Deposit Walkthrough

​Example values (1,000 USDC deposit on Ethereum mainnet)

​Permit Deposit Walkthrough

​Troubleshooting

​Next Steps

How Deposits Work

What You’ll Need

ABI Reference

DistributorCodeDepositor ABI

ERC-20 ABI (for approvals and allowance checks)

Accountant ABI (for slippage calculation)

Contract Method Reference

`deposit(depositAsset, depositAmount, minimumMint, to, distributorCode)`

`depositWithPermit(depositAsset, depositAmount, minimumMint, to, distributorCode, deadline, v, r, s)`

Distributor Codes

Calculating `minimumMint` (Slippage Protection)

Contract call

Calculation

Standard Deposit Walkthrough

Example values (1,000 USDC deposit on Ethereum mainnet)

Permit Deposit Walkthrough

Troubleshooting

Next Steps