Link External Wallet to User

Link an external wallet address to a user. Optionally provide a proof to verify ownership.

API scope required: users.create

PUT /2025-06-09/users/{userLocator}/linked-wallets/{address}

cURL

EVM

curl --request PUT \
  --url https://staging.crossmint.com/api/2025-06-09/users/{userLocator}/linked-wallets/{address} \
  --header 'Content-Type: application/json' \
  --header 'X-API-KEY: <api-key>' \
  --data '
{
  "chain": "base"
}
'

200

{
  "address": "0x1234567890abcdef1234567890abcdef12345678",
  "chain": "ethereum",
  "ownership": {
    "verified": true
  },
  "type": "external-wallet"
}

Authorizations

X-API-KEY · string · header · required

API key required for authentication

Path Parameters

userLocator · string · required

A user locator can be of the format:

• email:<email>
• userId:<userId>
• phoneNumber:<phoneNumber>
• twitter:<handle>
• x:<handle>

Examples:

"email:[e-mail]"

"userId:507f1f77bcf86cd799439011"

"userId:did:example:cm4lr5piw0h6t1bjho0onryql"

"phoneNumber:[phone]"

"twitter:johndoe"

"x:@johndoe"

address · string · required

Body

application/json

chain · enum<string> · required

The blockchain of the wallet

Available options: abstract, abstract-testnet, apechain, aptos, arbitrum, arbitrum-sepolia, arbitrumnova, arc, arc-testnet, astar-zkevm, avalanche, avalanche-fuji, base, base-goerli, base-sepolia, bsc, bsc-testnet, celo, celo-sepolia, chiliz, chiliz-spicy-testnet, coti, coti-testnet, curtis, ethereum, ethereum-goerli, ethereum-sepolia, flow, flow-testnet, hedera, hedera-testnet, hypersonic-testnet, lightlink, lightlink-pegasus, mantle, mantle-sepolia, mode, mode-sepolia, optimism, optimism-goerli, optimism-sepolia, plume, plume-testnet, polygon, polygon-amoy, polygon-mumbai, rari, rari-testnet, robinhood-chain, robinhood-chain-testnet, scroll, scroll-sepolia, sei-atlantic-2-testnet, sei-pacific-1, shape, shape-sepolia, skale-nebula, skale-nebula-testnet, solana, soneium, soneium-minato-testnet, space, space-testnet, stellar, story, story-testnet, sui, tempo, tempo-testnet, u2u-nebulas, u2u-solaris, verify-testnet, viction, viction-testnet, world-chain, world-chain-sepolia, xai, xai-sepolia-testnet, xion, zenchain-testnet, zkatana, zkyoto, zora, zora-goerli, zora-sepolia

Example:

"solana"

proof · object string

A signed message proving ownership of the wallet: a base64 signature by the wallet itself, or, for a Squads Smart Account vault on Solana, signatures by its members.

Show child attributes

Response

200 - application/json

Wallet linked to user

address · string · required

The wallet address

Example:

"0x1234567890abcdef1234567890abcdef12345678"

chain · enum<string> · required

The blockchain of the wallet

Available options: abstract, abstract-testnet, apechain, aptos, arbitrum, arbitrum-sepolia, arbitrumnova, arc, arc-testnet, astar-zkevm, avalanche, avalanche-fuji, base, base-goerli, base-sepolia, bsc, bsc-testnet, celo, celo-sepolia, chiliz, chiliz-spicy-testnet, coti, coti-testnet, curtis, ethereum, ethereum-goerli, ethereum-sepolia, flow, flow-testnet, hedera, hedera-testnet, hypersonic-testnet, lightlink, lightlink-pegasus, mantle, mantle-sepolia, mode, mode-sepolia, optimism, optimism-goerli, optimism-sepolia, plume, plume-testnet, polygon, polygon-amoy, polygon-mumbai, rari, rari-testnet, robinhood-chain, robinhood-chain-testnet, scroll, scroll-sepolia, sei-atlantic-2-testnet, sei-pacific-1, shape, shape-sepolia, skale-nebula, skale-nebula-testnet, solana, soneium, soneium-minato-testnet, space, space-testnet, stellar, story, story-testnet, sui, tempo, tempo-testnet, u2u-nebulas, u2u-solaris, verify-testnet, viction, viction-testnet, world-chain, world-chain-sepolia, xai, xai-sepolia-testnet, xion, zenchain-testnet, zkatana, zkyoto, zora, zora-goerli, zora-sepolia

Example:

"ethereum"

ownership · object · required

Ownership verification status of the wallet

Option 1

Option 2

Show child attributes

type · enum<string> · required

The type of linked wallet

Available options: external-wallet

Example:

"external-wallet"