Deposit addresses · FDUSD

First Digital USD deposit addresses for your users.

Give every one of your users a permanent First Digital USD address they can deposit to any time. It has no private key, and we pay the network fee to collect what lands on it. A Hong Kong-issued dollar with deep liquidity on BNB Chain, where a transfer costs a fraction of a cent.

Start building How deposit addresses works

FDUSD on 4 chains.

Enable the ones your users need. Each gives that user their own address, and enabling a new one later gives it to the users you already have.

EthereumERC-20

BNB ChainBEP-20

ArbitrumERC-20

SolanaSPL

FDUSD on Ethereum: Gas here is the highest of any chain on this list, so a payment has to clear a minimum amount to be worth collecting. The checkout shows that minimum to your payer before they choose Ethereum, and every other chain here is cheaper.
FDUSD on BNB Chain: USDT and USDC have 18 decimals on BNB Chain, where they have 6 almost everywhere else. Read decimals from the API rather than writing 6 into your code — getting it wrong is a silent error of twelve orders of magnitude.

Issuing a First Digital USD address.

Create the customer
One POST with your own user id as the reference. This is the record everything else hangs off.
Ask for an address per chain
One per (customer, chain), and it does not change. The same customer has the same address on every EVM chain, and you can show it again tomorrow without calling us.
Credit on deposit.confirmed
We watch every block, credit what lands, and pay the network fee to move it. Nothing we do behind an address ever changes what you are owed.

POST /v1/customers

curl https://api.molnpay.com/v1/customers \
  -H "Authorization: Bearer $MOLNPAY_SECRET_KEY" \
  -H "Idempotency-Key: user_4471" \
  -d reference_id="user_4471"

What you do not have to do.

Hold a FDUSD wallet, or guard a seed phrase for one. No address here has a private key.
Keep gas on hand. We pay the network fee on every chain FDUSD settles on.
Re-issue an address. One per user, per chain, and it does not change.
Watch every block yourself, or reconcile a reorg by hand.