Before you begin
- You have a Sumsub account and have integrated their KYC flow
- You have requested Meld enable Sumsub token sharing for your account
- You can obtain the Sumsub KYC token for each user
- You get a 1 time token from each onramp you use and add it to your Sumsub dashboard
- The onramp you plan to route to supports Sumsub token sharing (currently Mercuryo and Topper)
For sandbox testing details, see KYC testing.
Step 1: Sumsub Setup
This requires you to integrate Sumsub, and use them to KYC your user. Get a share token from each onramp you will pass the Sumsub KYC token to (Mercuryo and Topper for example) and add them in your Sumsub dashboard in the Partners tab.
Step 2: KYC the user via Sumsub
In order for your user to not be asked for any additional KYC information by the onramp, you must collect, at minimum,- Identity document (Driver’s license, ID card, Residence permit, or Passport)
- Selfie (advanced liveliness check)
- Applicant data
- First name
- Last name
- Country
- Street
- Street (line 2)
- City
- State
- Postcode
- Nationality
- TIN / SSN
- Tax residence country
- Date of birth
- Phone Number
network-partner-level2.You will have to fetch the KYC token of the user from Sumsub.

Step 3: Create a Meld customer
This step is required for the user to skip logging into the onramp, and is a one-time setup per user. CallPOST /accounts/customers and pass in the user’s first name, last name, email address, phone number, and birthday. Your request will look like this:
id in the response is now the Meld customerId of that user. You will need to pass this to Meld every time that user wants to make a transaction.
Step 4: Pass Meld the KYC token
If you send the user to an onramp that supports Sumsub token sharing, pass Meld the KYC token of the user when you callPOST /crypto/session/widget. Your request will look like this:
widgetUrl or serviceProviderWidgetUrl, then the user goes straight to the Mercuryo payment screen, as seen in this demo video.
And that’s it! Congrats, you are now using Meld’s Unified KYC product to enhance your users’ experience!