Card processing is handled by partners. Integration requires KYB and contract allowlisting with the partner before card payments are enabled. Sequence does not underwrite or operate the processor.
Supported processors: Transak and Forte. Coverage generally includes major EVM chains and is partner-dependent. Partners may consider adding new EVM chains based on opportunity. To begin, contact Sequence and we’ll introduce you to an appropriate partner.

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When to use Checkout SDK

  • You sell ERC-1155 / ERC-721 items and want a card option in addition to crypto.
  • You will complete partner KYB and allowlisting.
  • You want a drop-in modal that handles payment method selection and purchase.

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Installation

pnpm add @0xsequence/checkout @0xsequence/connect

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Basic setup

import { SequenceConnect } from '@0xsequence/connect'
import { SequenceCheckoutProvider } from '@0xsequence/checkout'
import { config } from './config'

export default function App() {
  return (
    <SequenceConnect config={config}>
      <SequenceCheckoutProvider>
        <YourRoutes />
      </SequenceCheckoutProvider>
    </SequenceConnect>
  )
}

​
Example: ERC-1155 primary sale

import { useAccount } from 'wagmi'
import { useERC1155SaleContractCheckout } from '@0xsequence/checkout'

export function BuyButton() {
  const { address } = useAccount()
  const { openCheckoutModal } = useERC1155SaleContractCheckout({
    chain: 137, // destination chainId
    contractAddress: '0xSaleContract',  // primary sale contract
    collectionAddress: '0xERC1155',     // collection
    wallet: address!,                   // recipient
    items: [{ tokenId: '1', quantity: '1' }],
    // Optional: restrict card providers if your integration requires it
    // creditCardProviders: ['transak', 'forte'],
    onSuccess: (txHash) => console.log('success', txHash),
    onError: (err) => console.error(err),
  })

  return <button onClick={() => address && openCheckoutModal()}>Buy</button>
}

​
Example: custom contract call

import { useAccount } from 'wagmi'
import { useSelectPaymentModal, type SelectPaymentSettings } from '@0xsequence/checkout'
import { encodeFunctionData } from 'viem'

export function CustomBuy() {
  const { address } = useAccount()
  const { openSelectPaymentModal } = useSelectPaymentModal()

  const onClick = () => {
    if (!address) return

    const chainId = 137
    const salesContract = '0xSaleContract'
    const currency = '0xUSDC'
    const collection = '0xERC1155'
    const price = '20000' // align with your contract's decimals

    const erc1155MintAbi = [{ /* ...mint signature matching your contract... */ }]
    const txData = encodeFunctionData({
      abi: erc1155MintAbi,
      functionName: 'mint',
      args: [address, /* tokenIds[] */, /* amounts[] */, /* data */, currency, price, /* proof */]
    })

    const settings: SelectPaymentSettings = {
      chain: chainId,
      targetContractAddress: salesContract,
      recipientAddress: address,
      currencyAddress: currency,
      collectionAddress: collection,
      price,
      collectibles: [{ tokenId: '1', quantity: '1' }],
      // creditCardProviders: ['transak', 'forte'],
      onSuccess: (txHash) => console.log('success', txHash),
      onError: (err) => console.error(err),
      txData,
    }

    openSelectPaymentModal(settings)
  }

  return <button onClick={onClick}>Buy (custom)</button>
}

​
Partner setup (cards)

1

Contact Sequence

Reach out to Sequence to discuss your use case; we will introduce you to Transak or Forte as appropriate.
2

Partner account & KYB

Create an account with a supported provider (e.g., Transak or Forte) and complete KYB.
3

Allowlist contracts

Ask the partner to allowlist the sale contract(s) you will charge through card flows.
4

Configure providers

Pass allowed providers via creditCardProviders if you need to scope usage to your approved partner(s).
5

Go live

Enable on major EVM chains per partner requirements and test a full purchase with a real card.
For crypto-only purchases, or to pay from “any token/chain”, use Trails. Checkout SDK focuses on the card path for NFT purchases and can coexist with Trails and wallet flows.

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References