When using transient payment intents, you can specify the timeframe in which
the customer must send payment by adjusting the expiresOn
setting.
USDC is a “stablecoin,” a cryptocurrency that provides a stable level of purchasing power. As such, it is a popular currency for online transactions, and your customers will want to use it as a payment medium. This guide will walk you through the basics of accepting USDC on your site. Here we use the Ethereum blockchain as an example, but the same steps apply to other currencies and chains as well.
Steps:
Once the customer reaches checkout and confirms they would like to pay with USDC on Ethereum, your system will send Circle a request to create a payment intent. Within this payment intent request you will specify the amount, currency, settlement currency, and chain.
Create a payment intent:
curl --location --request POST 'https://api-sandbox.circle.com/v1/paymentIntents' \
--header 'X-Requested-Id: ${GUID}' \
--header 'Authorization: Bearer ${YOUR_API_KEY}' \
--header 'Content-Type: application/json' \
--data-raw '{
"idempotencyKey": "17607606-e383-4874-87c3-7e46a5dc03dd",
"amount": {
"amount": "1.00",
"currency": "USD"
},
"settlementCurrency": "USD",
"paymentMethods": [
{
"type": "blockchain",
"chain": "ETH"
}
]
}'
{
"data": {
"id": "6e4d4047-db14-4c09-b238-1215aee50d03",
"amount": {
"amount": "1.00",
"currency": "USD"
},
"amountPaid": {
"amount": "0.00",
"currency": "USD"
},
"amountRefunded": {
"amount": "0.00",
"currency": "USD"
},
"settlementCurrency": "USD",
"paymentMethods": [
{
"type": "blockchain",
"chain": "ETH"
}
],
"paymentIds": [],
"timeline": [
{
"status": "created",
"time": "2022-07-21T20:13:35.579331Z"
}
],
"createDate": "2022-07-21T20:13:35.578678Z",
"updateDate": "2022-07-21T20:19:24.859052Z"
}
}
{
"clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522",
"notificationType": "paymentIntents",
"version": 1,
"customAttributes": { "clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522" },
"paymentIntent": {
"id": "6e4d4047-db14-4c09-b238-1215aee50d03",
"amount": { "amount": "1.00", "currency": "USD" },
"amountPaid": { "amount": "0.00", "currency": "USD" },
"amountRefunded": { "amount": "0.00", "currency": "USD" },
"settlementCurrency": "USD",
"paymentMethods": [{ "type": "blockchain", "chain": "ETH" }],
"paymentIds": [],
"refundIds": [],
"timeline": [
{ "status": "created", "time": "2022-07-21T20:13:35.579331Z" }
],
"createDate": "2022-07-21T20:13:35.578678Z",
"updateDate": "2022-07-21T20:13:35.578678Z"
}
}
For security reasons, we do not synchronously return the deposit blockchain address. To retrieve the blockchain deposit address, you have two options:
To receive webhook notifications, follow the steps in the
notifications quickstart.
After you subscribe to notifications, you will receive updates for the payment
intent whenever the resource is updated. In this case, when the
paymentMethods.address
is set, a notification is sent with a new timeline
object with a status
of pending
.
{
"clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522",
"notificationType": "paymentIntents",
"version": 1,
"customAttributes": { "clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522" },
"paymentIntent": {
"id": "6e4d4047-db14-4c09-b238-1215aee50d03",
"amount": { "amount": "1.00", "currency": "USD" },
"amountPaid": { "amount": "0.00", "currency": "USD" },
"amountRefunded": { "amount": "0.00", "currency": "USD" },
"settlementCurrency": "USD",
"paymentMethods": [
{
"type": "blockchain",
"chain": "ETH",
"address": "0x97de855690955e0da79ce5c1b6804847e7070c7f"
}
],
"fees": [
{ "type": "blockchainLeaseFee", "amount": "0.00", "currency": "USD" }
],
"paymentIds": [],
"refundIds": [],
"timeline": [
{ "status": "pending", "time": "2022-07-21T20:13:38.188286Z" },
{ "status": "created", "time": "2022-07-21T20:13:35.579331Z" }
],
"createDate": "2022-07-21T20:13:35.578678Z",
"updateDate": "2022-07-21T20:13:38.186831Z",
"expiresOn": "2022-07-21T21:13:38.087275Z"
}
}
If you prefer to poll
get a payment intent,
you can send get
request until you receivepaymentMethods.address
.
Retrieve payment intent:
curl --location --request GET 'https://api-sandbox.circle.com/v1/paymentIntents/{id}' \
--header 'X-Requested-Id: ${GUID}' \
--header 'Authorization: Bearer ${YOUR_API_KEY}'
{
"data": {
"id": "6e4d4047-db14-4c09-b238-1215aee50d03",
"amount": {
"amount": "1.00",
"currency": "USD"
},
"amountPaid": {
"amount": "0.00",
"currency": "USD"
},
"amountRefunded": {
"amount": "0.00",
"currency": "USD"
},
"settlementCurrency": "USD",
"paymentMethods": [
{
"type": "blockchain",
"chain": "ETH",
"address": "0x97de855690955e0da79ce5c1b6804847e7070c7f"
}
],
"fees": [
{ "type": "blockchainLeaseFee", "amount": "0.00", "currency": "USD" }
],
"paymentIds": [],
"refundIds": [],
"timeline": [
{ "status": "pending", "time": "2022-07-21T20:13:38.188286Z" },
{ "status": "created", "time": "2022-07-21T20:13:35.579331Z" }
],
"createDate": "2022-07-21T20:13:35.578678Z",
"updateDate": "2022-07-21T20:13:38.186831Z",
"expiresOn": "2022-07-21T21:13:38.087275Z"
}
}
Once you receive the deposit address via paymentMethods.address
, you’ll
provide it to the customer along with the amount and currency to be paid. You
can present the address two ways:
The customer then sends payment from their wallet (custodial or non-custodial).
When using transient payment intents, you can specify the timeframe in which
the customer must send payment by adjusting the expiresOn
setting.
Once Circle obtains payment on-chain, we create a Payment resource linked to the Payment Intent created earlier and update the status of that Payment Intent. Your firm will then receive payment via the method specified.
{
"clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522",
"notificationType": "paymentIntents",
"version": 1,
"customAttributes": { "clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522" },
"paymentIntent": {
"id": "6e4d4047-db14-4c09-b238-1215aee50d03",
"amount": { "amount": "1.00", "currency": "USD" },
"amountPaid": { "amount": "1.00", "currency": "USD" },
"amountRefunded": { "amount": "0.00", "currency": "USD" },
"settlementCurrency": "USD",
"paymentMethods": [
{
"type": "blockchain",
"chain": "ETH",
"address": "0x97de855690955e0da79ce5c1b6804847e7070c7f"
}
],
"fees": [
{ "type": "blockchainLeaseFee", "amount": "0.00", "currency": "USD" },
{ "type": "totalPaymentFees", "amount": "0.01", "currency": "USD" }
],
"paymentIds": ["66c56b6a-fc79-338b-8b94-aacc4f0f18de"],
"refundIds": [],
"timeline": [
{
"status": "complete",
"context": "paid",
"time": "2022-07-21T20:19:24.861094Z"
},
{ "status": "pending", "time": "2022-07-21T20:13:38.188286Z" },
{ "status": "created", "time": "2022-07-21T20:13:35.579331Z" }
],
"createDate": "2022-07-21T20:13:35.578678Z",
"updateDate": "2022-07-21T20:19:24.859052Z",
"expiresOn": "2022-07-21T21:13:38.087275Z"
}
}
{
"clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522",
"notificationType": "payments",
"version": 1,
"customAttributes": { "clientId": "f1397191-56e6-42fd-be86-0a7b9bd91522" },
"payment": {
"id": "66c56b6a-fc79-338b-8b94-aacc4f0f18de",
"type": "payment",
"status": "paid",
"amount": { "amount": "1.00", "currency": "USD" },
"fees": { "amount": "0.01", "currency": "USD" },
"createDate": "2022-07-21T20:16:35.092Z",
"updateDate": "2022-07-21T20:19:24.719Z",
"merchantId": "f1397191-56e6-42fd-be86-0a7b9bd91522",
"merchantWalletId": "1000999922",
"paymentIntentId": "6e4d4047-db14-4c09-b238-1215aee50d03",
"settlementAmount": { "amount": "1.00", "currency": "USD" },
"fromAddresses": {
"chain": "ETH",
"addresses": ["0x0d4344cff68f72a5b9abded37ca5862941a62050"]
},
"depositAddress": {
"chain": "ETH",
"address": "0x97de855690955e0da79ce5c1b6804847e7070c7f"
},
"transactionHash": "0x7351585460bd657f320b9afa02a52c26d89272d0d10cc29913eb8b28e64fd906"
}
}
Retrieve a payment intent:
curl --location --request GET 'https://api-sandbox.circle.com/v1/paymentIntents/{id}' \
--header 'X-Requested-Id: ${GUID}' \
--header 'Authorization: Bearer ${YOUR_API_KEY}'
{
"data": {
"id": "6e4d4047-db14-4c09-b238-1215aee50d03",
"amount": {
"amount": "1.00",
"currency": "USD"
},
"amountPaid": {
"amount": "1.00",
"currency": "USD"
},
"amountRefunded": {
"amount": "0.00",
"currency": "USD"
},
"settlementCurrency": "USD",
"paymentMethods": [
{
"type": "blockchain",
"chain": "ETH",
"address": "0x97de855690955e0da79ce5c1b6804847e7070c7f"
}
],
"fees": [
{
"type": "blockchainLeaseFee",
"amount": "0.00",
"currency": "USD"
},
{
"type": "totalPaymentFees",
"amount": "0.01",
"currency": "USD"
}
],
"paymentIds": ["66c56b6a-fc79-338b-8b94-aacc4f0f18de"],
"refundIds": [],
"timeline": [
{
"status": "complete",
"context": "paid",
"time": "2022-07-21T20:19:24.861094Z"
},
{
"status": "pending",
"time": "2022-07-21T20:13:38.188286Z"
},
{
"status": "created",
"time": "2022-07-21T20:13:35.579331Z"
}
],
"createDate": "2022-07-21T20:13:35.578678Z",
"updateDate": "2022-07-21T20:19:24.859052Z",
"expiresOn": "2022-07-21T21:13:38.087275Z"
}
}
Retrieve a payment:
curl --location --request GET 'https://api-sandbox.circle.com/v1/payments/{id}' \
--header 'X-Requested-Id: ${GUID}' \
--header 'Authorization: Bearer ${YOUR_API_KEY}'
{
"data": {
"id": "66c56b6a-fc79-338b-8b94-aacc4f0f18de",
"type": "payment",
"status": "paid",
"amount": {
"amount": "1.00",
"currency": "USD"
},
"fees": {
"amount": "0.01",
"currency": "USD"
},
"createDate": "2022-07-21T20:16:35.092852Z",
"updateDate": "2022-07-21T20:19:24.719313Z",
"merchantId": "f1397191-56e6-42fd-be86-0a7b9bd91522",
"merchantWalletId": "1000999922",
"paymentIntentId": "6e4d4047-db14-4c09-b238-1215aee50d03",
"settlementAmount": {
"amount": "1.00",
"currency": "USD"
},
"fromAddresses": {
"chain": "ETH",
"addresses": ["0x0d4344cff68f72a5b9abded37ca5862941a62050"]
},
"depositAddress": {
"chain": "ETH",
"address": "0x97de855690955e0da79ce5c1b6804847e7070c7f"
},
"transactionHash": "0x7351585460bd657f320b9afa02a52c26d89272d0d10cc29913eb8b28e64fd906"
}
}
For blockchains that require a 'memo' or 'address tag' (XLM, HBAR, etc.), the
optional addressTag
field will be present in the depositAddress
object.
Call the GET /payment/presign
endpoint to fetch the typed message. The two
required parameters are paymentIntentId
, which can be retrieved from the
GET /paymentIntent
response or webhook notification; and endUserAddress
which is the consumer wallet address.
curl --location 'https://api-sandbox.circle.com/v1/payments/presign?paymentIntentId=6e4d4047-db14-4c09-b238-1215aee50d03&endUserAddress=0x8381470ED67C3802402dbbFa0058E8871F017A6F' \
--header 'X-Requested-Id: ${GUID}' \
--header 'Authorization: Bearer ${YOUR_API_KEY}'
{
"data": {
"typedData": {
"domain": {
"name": "USD Coin",
"verifyingContract": "0x07865c6e87b9f70255377e024ace6630c1eaa37f",
"version": "2",
"chainId": 5
},
"message": {
"from": "0x8381470ED67C3802402dbbFa0058E8871F017A6F",
"to": "0xdB055877e6c13b6A6B25aBcAA29B393777dD0a73",
"value": "5003456",
"validAfter": 1675317371,
"validBefore": 1675107967,
"nonce": "0x4f716a578b96592599c3ca7b2a46453df87511d4809f608cec982d6e83632604"
},
"totalAmount": {
"amount": "3.14",
"currency": "USD"
},
"feeChargeModel": "endUser",
"networkFeeQuote": {
"quoteId": "5d0bb4e7-bd83-44dd-b8f5-53ddd5f35a3a",
"amount": {
"amount": "3.14",
"currency": "USD"
},
"expiresAt": "2023-02-02T06:01:21.152737680Z"
},
"types": {
"EIP712Domain": [
{
"name": "name",
"type": "string"
},
{
"name": "version",
"type": "string"
},
{
"name": "chainId",
"type": "uint256"
},
{
"name": "verifyingContract",
"type": "address"
}
],
"TransferWithAuthorization": [
{
"name": "from",
"type": "address"
},
{
"name": "to",
"type": "address"
},
{
"name": "validAfter",
"type": "uint256"
},
{
"name": "validBefore",
"type": "uint256"
},
{
"name": "nonce",
"type": "byte32"
}
]
},
"primaryType": "TransferWithAuthorization"
}
}
}
You will need to trigger the customer’s wallet using the response from
/presign
.
For example, if you use the signTypedData function from wagmi, you will need to fill out the domain, types and values fields.
Once the customer signs into the wallet, you will receive a string of raw signatures.
With a customer’s raw signature, Circle can create a crypto payment with the
POST /payment/crypto
endpoint.
curl --location 'https://api-sandbox.circle.com/v1/payments/crypto' \
--header 'X-Requested-Id: ${GUID}' \
--header 'Authorization: Bearer ${YOUR_API_KEY}' \
--header 'Content-Type: application/json' \
--data '{
"idempotencyKey": "ba943ff1-ca16-49b2-ba55-1057e70ca5c7",
"paymentIntentId": "4e9fa5b1-3964-4f02-a7ba-811cc5d94be1",
"protocolMetadata": {
"type": "TransferWithAuthorization",
"metaTxNonce": "0xfdb476566b75311fdd14444e6a77630c36e653a3e255adcaa7c34f3babc1de76",
"signatureValidAfter": "1675104393",
"signatureValidBefore": "1675107967",
"rawSignature": "0xcff7ef7a24b88d83fa3d6e81b41c9cef19cc0119c085a6ef98cb1b6bc9436a9f18dcb2d46b9cb4d31a7031466b450bbe1e6c0230c5503c7a68e04055b4be0cbc1b"
},
"amount": {
"amount": "3.14",
"currency": "USD"
},
"source": {
"address": "0xdB055877e6c13b6A6B25aBcAA29B393777dD0a73",
"type": "blockchain"
},
"destination": {
"address": "0xda1ab716f7f7b3cb036a7fd74e5ca852126834c1",
"chain": "ETH"
},
"quoteId": "c6ac001e-9812-4bc1-8dc3-1549b5adaa23"
}'
{
"data": {
"id":"27827c45-6a3e-4012-8eaa-f6d712f70c2e",
"type":"payment",
"status":"pending",
"amount":{
"amount":"10.00",
"currency":"USD"
}
"createDate":"2023-02-14T01:21:07.116369Z",
"updateDate":"2023-02-14T01:21:07.116371Z",
"merchantId":"a49f9b1d-75e0-44a9-b8d2-4293b3f11ebd",
"merchantWalletId":"1000563095",
"paymentIntentId":"dfcf96ab-dd3f-417e-b009-ef899ee4e8da",
"fromAddresses":{
"chain":"ETH",
"addresses":[
"0xbdE3d06b700A5f622767c85e79e42014C5376B6B"
]
}
"depositAddress":{
"chain":"ETH",
"address":"0x5f1090b5db3e00e13e94b93055b3d1c4254e1720"
}
}
}