At a glance
Optimism on Paymos
Supported assets
- USDT Tether USD
- USDC USD Coin
Confirmation speed
| Up to $100 | 5 blocks |
| Up to $1,000 | 15 blocks |
| Up to $10,000 | 30 blocks |
| Larger amounts | 100 blocks |
Paymos accepts USDT and USDC on Optimism. Each invoice gets its own address, each asset keeps its own merchant balance, and a confirmed payment is credited in the token the customer chose — never turned into the other one.
Supported assets on Optimism
Optimism carries USDT and USDC. USD1, DAI and XAUT are not part of its route set, and ETH pays the network fee rather than the invoice.
Both stablecoins can sit on the same checkout at once, and the customer picks the one their wallet holds. A USDC balance on Base, or USDT on Arbitrum, belongs to a different route and does not close an Optimism invoice.
How an Optimism payment works
- The merchant creates an invoice through checkout, Payment Links, POS, a CMS plugin, Low-Code SDK, or REST API.
- The customer selects USDT or USDC on Optimism.
- Paymos assigns a dedicated deterministic address.
- The customer sends the exact amount over Optimism.
- Paymos detects the transfer and waits for the confirmations that amount requires.
- The confirmed asset is credited to the balance for that token, not to a shared pot.
HMAC-SHA256-signed webhooks report every status change, which keeps the order and the payment in step without a merchant-run chain listener.
Confirmations depend on network and amount
The wait is counted in blocks, and how many blocks depends on what the invoice is worth. On a network running normally that comes to about ten seconds up to $100 and about three and a half minutes above $10,000, with roughly thirty seconds and a minute for the two steps in between.
None of that is a delivery guarantee. Use the Paymos invoice status before fulfillment: a broadcast in the payer's wallet is not the same event as a settled invoice.
ETH gas and Paymos fees
The payer's wallet pays the Optimism network fee in ETH. It goes to the network rather than to Paymos and moves with demand, which is why no fixed figure appears on this page. A wallet holding nothing but stablecoins cannot send them.
Paymos covers the network cost of accepting and consolidating the payment. Standard pricing is 1.0% per settled invoice; Enterprise is 0.3% on request. There is no setup fee, monthly fee, minimum volume, reserve, rolling reserve, or charge for unpaid, expired or cancelled invoices.
Same-asset settlement
A USDT invoice settles in USDT and a USDC invoice settles in USDC. There is no automatic exchange between the two and no charge folded into a rate.
Two assets therefore mean two balances, not two integrations, and each balance also collects the same token from the other supported networks. On withdrawal, the merchant selects an available network and a whitelisted destination.
Paymos adds no processing commission to withdrawals. Any network fee for the chosen payout network is shown in advance, and it sits below the chain's own charge for that send.
When to enable Optimism
Optimism is worth offering when customers hold either stablecoin there and keep ETH on the same network for the fee. It sits beside Arbitrum, Base and the rest inside one integration.
Do not send a customer to a chain because its name sounds cheap. The usable route is the one where their asset and their gas are in the same wallet.
Integration and custody controls
Hosted Checkout, Embedded Checkout, Payment Links and Low-Code SDK show the asset, network, amount, address and QR data. H2H REST API, POS and official CMS plugins support other workflows.
Outgoing transactions are signed on isolated infrastructure. Withdrawal whitelisting separately restricts payout destinations.
Frequently asked questions
Which assets can Paymos accept on Optimism?
Both USDT and USDC, each settling into its own merchant balance.
Can USDC from Base pay an Optimism invoice?
No. Base and Optimism are separate networks, and the invoice names the one it accepts.
Does the customer need ETH?
The sending wallet needs ETH on Optimism for the network fee. It never becomes part of the amount owed.
How long does an Optimism payment take?
About ten seconds on a small invoice and about three and a half minutes on one above $10,000, when the network is running normally.
Does Paymos convert the payment?
No. USDT is credited as USDT, USDC as USDC, and neither is exchanged for the other.
How do I enable Optimism payments?
Enable the supported Optimism assets in your integration. Compare the supported networks or review how crypto gas fees work.