At a glance
Arbitrum on Paymos
Supported stablecoins
- USDT Tether USD
- USDC USD Coin
Confirmation speed
| Up to $100 | 40 blocks |
| Up to $1,000 | 120 blocks |
| Up to $10,000 | 240 blocks |
| Larger amounts | 800 blocks |
Why Arbitrum for crypto payments
Arbitrum One is the largest Ethereum Layer-2 by total value locked and daily DeFi volume. Its customers skew crypto-fluent — Aave, GMX, Camelot, and Pendle users who hold real stablecoin balances and would rather not pay Ethereum L1 gas for an ordinary transfer. For a merchant, it's the right rail when your audience overlaps with DeFi power users or with B2B counterparties already on Arbitrum. It's less common for pure retail (where Polygon, BSC, and Tron dominate), but for the segment that treats Arbitrum as "their" L2, accepting it removes a bridge step.
Supported stablecoins on Arbitrum
The panel above shows what's live: native USDC and native USDT, both ERC-20. One asset to watch for is bridged USDC.e — the older wrapper from before Circle issued USDC directly on Arbitrum. Paymos credits native USDC only. Most wallets now default to it, so USDC.e is rare; a customer still holding it swaps to native first.
How confirmations work on Arbitrum
Arbitrum confirms a block roughly every 250ms — fast enough that confirmation counts climb into the hundreds while wall-clock time stays in seconds. Depth scales with the amount: a small ticket needs only a shallow margin and clears almost at once, while a five-figure transfer waits for a much deeper count to guard against a sequencer hiccup or a rollup-state reorg. On a chain this fast, even that deeper wait lands inside a couple of minutes.
Fees and gas
The customer pays the network fee in ETH on Arbitrum. A stablecoin transfer currently costs a few cents — orders of magnitude below the same transfer on Ethereum mainnet, which is the whole reason the L2 exists. The catch: ETH is still the gas token, so a wallet carrying USDC but no ETH on Arbitrum can't broadcast until it tops up a few cents of it.
Paymos pricing on Arbitrum: 1.0% Standard, 0.3% Enterprise on request. Acceptance and the gas to sweep the payment both sit inside that 1.0% — there is no separate line for either. On withdrawal Paymos takes 0 commission; the merchant pays only a reduced network fee, set below what the chain itself charges, with Paymos covering the rest. Payouts settle in USDC or USDT to a whitelisted wallet.
Compared to a typical crypto gateway
Most gateways hard-code one confirmation count for an L2 and apply it to a $20 order and a $20,000 invoice alike — either over-waiting on the small one or under-securing the large one. Paymos scales the count with the amount, so a coffee-sized payment doesn't sit behind the safety margin a treasury transfer needs. On the integration side, the signing and delivery contract is identical to every other Paymos chain: each state change posts a webhook signed with HMAC-SHA256, a missed endpoint is retried 11 times over roughly 32 hours, and a repeated external_order_id returns the original invoice instead of creating a duplicate — no idempotency header to track.
What we don't do on Arbitrum
The accepted set on Arbitrum is USDC and USDT — no DAI, USD1, or XAUT here, because their issuers didn't deploy them on this rollup. Bridge-wrapped variants of any token are out too; Paymos credits the canonical asset only. We don't auto-swap or off-ramp to fiat — your balance stays in the exact stablecoin the buyer sent. The buyer's ETH for gas is on them; Paymos doesn't top up customer wallets. And the optimistic-rollup 7-day window to exit funds to Ethereum L1 never touches you: payments land and balances withdraw on Arbitrum itself, and whether to consolidate up to L1 later is your treasury's call.
Frequently asked questions
What's the difference between Arbitrum and Optimism mechanically?
Both are optimistic rollups, and the fraud-proof internals differ more than the day-to-day experience does. Arbitrum's Nitro stack proves disputed state by compiling its prover to WebAssembly; Optimism's Cannon proves it over a MIPS target. For a buyer or a merchant the difference is invisible — both settle stablecoin transfers the same way. Choose the rollup your audience already lives on, not the proof system underneath it.
Should I accept USDC on Arbitrum or USDT?
Accept both — there's no setup penalty for it, and the buyer self-selects at checkout. If you must pick one, USDC carries slightly deeper liquidity on Arbitrum and skews toward US and EU buyers, while USDT skews global. Whichever balances you accrue, they withdraw the same way.
Is the 7-day withdrawal a problem for my business?
Not for payment acceptance. You receive on Arbitrum, hold balance on Arbitrum, and can withdraw to a whitelisted Arbitrum address. The 7-day rule only applies to canonical withdrawals all the way to Ethereum L1 — which most merchants don't do directly. Third-party bridges can consolidate sooner if you need it.
What gas token does Arbitrum use?
ETH — the same asset as Ethereum L1, just held on the Arbitrum side. A buyer paying USDC needs a sliver of Arbitrum ETH to cover the fee; a few cents is plenty. Unlike a Coinbase-managed flow, no wallet auto-buys it here, so the buyer either bridges a little ETH down from L1 or keeps a small float on Arbitrum.
Can a customer pay me from Binance to Arbitrum?
Yes. Binance supports USDC and USDT withdrawals to Arbitrum. The customer picks Arbitrum as the network on withdrawal; funds arrive at your Paymos deposit address.
Is Arbitrum decentralized?
Partially, and the trend is toward more. The protocol is open-source and validation is permissionless — anyone can run a validator and challenge an invalid state. The one centralized piece is the sequencer that orders transactions, run today by the Arbitrum Foundation, with a published roadmap to decentralize it and a censorship-timeout escape hatch already live in the interim. For accepting payments, what matters is that the chain confirms and stays final, which it does regardless of who currently runs the sequencer.