Gas Fees
Every blockchain transaction requires a gas fee -- a small amount of the chain's native token paid to the network validators who process the transaction. This page explains how gas fees work with DirectCryptoPay payments.
Who Pays Gas Fees?
The customer pays the gas fee. When a customer signs a transaction to pay a merchant, their wallet deducts:
- The payment amount (in the selected token, e.g., USDC)
- The gas fee (in the chain's native token, e.g., ETH on Ethereum, POL on Polygon)
The merchant receives the full payment amount. DCP does not charge any additional fees.
Example: A customer pays $50 in USDC on Polygon. The customer's wallet sends exactly $50 in USDC to the merchant. The customer also pays ~$0.005 in POL as a gas fee to the Polygon network. The merchant receives the full $50.
Gas fees vary significantly between chains. This is often the primary factor in a customer's chain selection.
| Chain | Typical Gas Cost (Token Transfer) | Typical Gas Cost (Native Transfer) |
|---|---|---|
| Ethereum | $1 - $5 | $0.50 - $3 |
| Polygon | < $0.01 | < $0.005 |
| BNB Chain | $0.02 - $0.05 | $0.01 - $0.03 |
Ethereum gas fees fluctuate. During periods of high network congestion, Ethereum gas fees can spike significantly. Polygon and BNB Chain remain consistently low regardless of congestion.
- Ethereum -- Fees are higher because Ethereum L1 has limited throughput and high demand
- Polygon -- Fees are near-zero because Polygon processes transactions on a sidechain with higher throughput
- BNB Chain -- Fees are low because BNB Chain uses a more centralized consensus mechanism with fewer validators
Native Token vs ERC-20 Transfer
Sending a chain's native token (ETH, POL, BNB) costs less gas than sending an ERC-20 token (USDC, USDT). This is because ERC-20 transfers involve executing a smart contract, while native token transfers are simpler operations.
| Transfer Type | Gas Units (Approximate) |
|---|---|
| Native token (ETH, POL, BNB) | ~21,000 |
| ERC-20 token (USDC, USDT) | ~65,000 |
Despite the higher gas units, ERC-20 transfers on Polygon and BNB Chain still cost fractions of a cent.
Customer Experience
The widget displays the estimated gas fee to the customer before they sign the transaction. The customer's wallet (MetaMask, Rabby, etc.) also shows the gas fee in the confirmation dialog.
If a customer does not have enough native tokens for gas, the transaction will fail. The widget will display an error message.
Tip for Customers: Always keep a small balance of the chain's native token (ETH, POL, or BNB) for gas fees, even when paying with stablecoins like USDC.
As a merchant, gas fees have no impact on you:
- You receive the full payment amount -- Gas is paid by the customer separately
- No DCP transaction fees -- DCP does not add any per-transaction fees
- Your only cost is the DCP subscription -- A flat monthly fee regardless of transaction volume
Reducing Customer Gas Costs
To give your customers the lowest gas experience:
- Enable Polygon -- Near-zero gas fees make it ideal for any payment amount
- Enable BNB Chain -- Low fees and popular with Binance users
- Accept stablecoins -- USDC on Polygon gives customers stable value with minimal gas
- Let customers choose -- The widget lets customers pick their preferred chain, so they can optimize for cost themselves