A contract address is not a wallet
30 October 2026
A payment request went out with a payout address that passes every check this site had: right prefix, right length, right base58 checksum. Three providers refused to create the order, each in its own words.
Changelly createTransaction [-32602]: Invalid payout address GhostSwap create: HTTP 400 Invalid payout address FixedFloat create: Public contract address (code 301)Only the third says anything useful. The address was the Tether TRC-20 contract. It is a real address on Tron and it is not a wallet: anything sent to it is gone, and no amount of checksum arithmetic says so.
Where the error arrived is the actual fault
A merchant builds a request, the link travels, and days later a stranger opens it and presses a button. The provider checks the address at that moment — at order creation, in front of the payer, about a mistake somebody else made.
The person who could fix it never saw the error. The person who saw it could do nothing about it. That is the shape of every address fault on this path, and it is the reason the check belongs in the field where the address is typed rather than at the end of the chain.
Why a general answer was not available
Deciding whether an arbitrary address is a contract means asking the chain, and this check runs in a text field with no network of its own. So the list is short and specific: the contracts people actually paste, which are the ones sitting next to the word “contract” on every block explorer and token page — exactly where somebody looking for “the USDT address” ends up.
Every entry was taken from a provider’s own catalogue rather than typed from memory, because a list of addresses assembled by hand is a list with a typo in it.
What a checksum is and is not
Base58check catches a mistyped character. It says nothing about whether the thing at the other end can receive money, and this site had been treating the first as evidence of the second. Both tests exist now and they answer different questions: one asks whether the address was copied correctly, the other whether it is a place at all.
Every figure above can be checked against the providers yourself — no account, no sign-up, and nothing is held for you at any point.