Wallet address in crypto payments
A wallet address is the public string of letters and numbers that identifies where cryptocurrency should be sent on a particular blockchain network, much as an IBAN identifies a bank account. You meet one in a casino or sportsbook cashier twice: when the site shows you its deposit address, and when you paste in your own address to withdraw. It is safe to share, because it only receives funds. The private key that spends them is a different thing entirely, and that one you never give anyone.
How a wallet address is built
An address is not random text. It is derived from a public key or a script, given a prefix that tells the wallet what kind of address it is, and finished with a checksum that catches most typing errors.
Bitcoin
Bitcoin has several formats in use at once. Legacy addresses start with 1, script addresses often used for multisig or wrapped SegWit start with 3, and modern addresses start with bc1: bc1q for native SegWit and bc1p for Taproot. A native SegWit key-hash address runs to 42 characters, while the script-hash version runs to 62. Legacy formats use Base58Check, which hashes the address data twice with SHA-256 and keeps the first four bytes as the checksum.
Ethereum and EVM chains
An Ethereum address is 0x followed by 40 hexadecimal characters, which is 20 bytes taken from the Keccak-256 hash of the public key. Under EIP-55, the mix of capital and lower-case letters is itself a checksum, so a wallet can reject a mistyped address before anything moves.
One catch matters more than the rest.
Polygon, BNB Smart Chain and other EVM networks use the identical 0x format, so the same string can be valid on several chains at once, and the address alone will not tell you which network a cashier expects.
Where you meet it in the cashier
On a deposit, the site generates an address for the coin and the network you pick from a dropdown. Change the network and the address usually changes with it, so the address belongs to that selection rather than to the coin in general.
Some coins add a second field. XRP uses a destination tag, while Stellar, Cosmos and a few others use a memo, because the receiving platform holds one shared address and sorts customers by that number. Leave it off and the transaction still confirms on the blockchain, but the funds land on the shared address without being credited to your balance. Exchange help pages describe recovery as a manual support process that needs the transaction ID and proof you control the sending address, and none of them guarantee it. A wrong tag is worse than a missing one, since it can match another customer.
On a withdrawal, you supply the address. The step where crypto cash-outs most often stall is the same one as with cards: the site’s ID and source-of-funds checks, which run before anything is broadcast to the network. Whether an operator also requires you to whitelist an address in advance, or caps withdrawals to new addresses, varies from site to site and sits in its payment terms.
Once a withdrawal confirms on-chain, there is no chargeback.
What a wallet address is often confused with
The most dangerous confusion is with the private key or seed phrase. The address receives; the key spends. Any cashier, support agent or “verification” form asking for your seed phrase is not doing KYC, and the polite term for it is theft.
The address is also not the transaction ID. A TxID, or hash, identifies one payment and is what support asks for when a deposit goes missing, while the address stays the same across many payments. Nor is it the network: USDT, for example, exists on more than one chain, and an address shown for one does not accept the token sent over another. Sending on the wrong network to an address nobody controls there is usually permanent.
What I check first in any guide or cashier is whether it names the network next to the address, because an address without one is half an instruction.
The other habit worth keeping is comparing the whole string after pasting it. Address-poisoning scams plant look-alike addresses in your history that match the first and last few characters, so checking the ends alone is exactly the check they are designed to pass. Checksums catch typing slips, not a valid address belonging to somebody else.
