Send USDC from EWX to Polkadot Asset Hub

This tutorial sends Polkadot Asset Hub USDC from Energy Web X (EWX) to Polkadot Asset Hub (AssetHub) using a pre-built XCM reserve transfer call.

Key facts you must know

• Asset Hub USDC uses 6 decimals.

  • 1 USDC = 1,000,000 base units.

• You will replace two fields before submitting:

  • the recipient public key (AccountId32)

  • the USDC amount (base units)

Safety tip: Do a small test first (e.g., 1–2 USDC) before sending a large amount.

Step 1 — Check your USDC balance on EWX (optional)

Open the EWX explorer and paste your EWX account address:

https://energywebx.subscan.io/account/

Step 2 — Open Polkadot.js “Decode call” on EWX (transaction-enabled RPC)

Use this Polkadot.js Apps link (EWX RPC):

https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fwnp-rpc.mainnet.energywebx.com%2F#/extrinsics/decode

Step 3 — Paste the pre-built hex call

In “hex-encoded call”, paste this exact value:

0x1f0203010100a10f0300010100b067874261d04930c1b09037ebc472946333465e7d0cd3498f406dc3bba8d86e030400010300a10f043205e5140002093d0000000000

Verify (do not skip)

Confirm the decoded call shows:

• destination is Polkadot Asset Hub (Parachain 1000)

• the asset points to USDC on Asset Hub (Asset ID 1337)

• the call contains a Fungible amount you can edit

If anything looks different, STOP and do not sign.

Step 4 — Get the recipient “hex public key” (32-byte AccountId32)

Open Polkadot.js Utilities on the same EWX RPC:

https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fwnp-rpc.mainnet.energywebx.com%2F#/utilities

Choose the destination address

• If you are sending to the same wallet account on Asset Hub, use your own address.

• If you are sending to a CEX, use your exchange’s deposit address for:

  • “USDC (Polkadot Asset Hub)”

Convert address → hex public key

In Utilities, use the tool that converts an address to hex (often labeled “Address to Hex”):

1. Paste the destination address

2. Copy the output hex public key

It should look like:

• starts with 0x

• followed by 64 hex characters (32 bytes)

Step 5 — Fill recipient + amount on the Submission tab

Go back to the Decode page and click Submission.

A) Paste the recipient public key

Find the field:

• AccountId32 → id: [u8;32]

Paste the recipient hex public key (from Step 4).

B) Enter the USDC amount (base units)

Find:

• Fungible: Compact

Enter the amount in base units (6 decimals):

USDC_to_send × 1,000,000 = base_units

Examples:

• 1 USDC → 1000000

• 10 USDC → 10000000

• 12.34 USDC → 12340000

Step 6 — Submit the transaction

1. Click Submit Transaction

2. Approve/sign in your wallet

Step 7 — Confirm on Asset Hub explorer

After it processes, check the recipient address on Asset Hub explorer:

https://assethub-polkadot.subscan.io/account/

You should see the USDC balance on Asset Hub.