Networks, fees, and the wrong-network mistake

Bitcoin does one thing and has changed very little in doing it. There is no smart contract layer in ordinary use, so there are no tokens to send by mistake: if you are on Bitcoin, you are sending bitcoin.

A block arrives roughly every ten minutes, and that average hides a lot of variance — twenty minutes between blocks is unremarkable. Nothing is ever mathematically final; instead each new block makes reversal more expensive, which is why exchanges wait for a number of confirmations before crediting a deposit. Three is common for small amounts, six for larger ones, and the number is the platform's policy rather than a rule of the network.

Fees are paid in bitcoin and priced per unit of transaction size, not per amount sent, so moving a large sum costs the same as a small one. They rise when the network is busy. If you send at a fee that is too low the transaction simply waits, sometimes for days, and it is not lost — it is queued.

Ethereum is the network the others are usually compared to. Tokens follow the ERC-20 standard, addresses start with 0x, and fees are paid in ether — which is the detail that catches people out: you can hold a thousand dollars of USDC and be unable to move it because you have no ETH for the fee.

A block is produced every twelve seconds, but a block is not the end of the story. Ethereum reaches actual finality after two epochs, roughly thirteen minutes, and that is the point past which reversing a transaction would require destroying an enormous amount of staked value. Exchanges usually credit deposits well before then.

Fees rise and fall with demand and can move by an order of magnitude within a day. There is no fixed answer to what a transfer costs; check before you send rather than after.

Base is a rollup: it processes transactions itself and periodically posts the compressed result to Ethereum, which is what makes it inherit Ethereum's security while costing a tiny fraction as much. Fees are paid in ether, and they are small enough that most people stop thinking about them.

The part that surprises people is the exit. Moving funds onto Base is quick. Moving them back to Ethereum through the official bridge takes about seven days, because optimistic rollups allow a challenge window in which an incorrect batch can be disputed. That is not a queue or a delay you can pay to skip; it is the security model. Third-party bridges offer instant exits by fronting you the money and charging for it.

Arbitrum works on the same principle as Base and carries much of the same activity. Fees are paid in ether and are negligible for ordinary transfers; the seven-day challenge window on withdrawals back to Ethereum applies here too.

Where it differs is history and breadth: Arbitrum has been running longer and hosts a wider set of applications, which mostly matters if you are using them rather than simply holding.

BNB Chain uses the same address format and the same wallet software as Ethereum, but it is a different network with its own validators and its own native asset. Tokens here follow BEP-20, which is ERC-20 under another name, and fees are paid in BNB.

The Maxwell hardfork, live on mainnet since 30 June 2025, cut block time to 0.75 seconds and brought fast finality to about 1.9 seconds. In practice a transfer confirms while you are still looking at the screen.

The validator set is smaller than Ethereum's, which is part of why it is faster and cheaper. Whether that trade matters to you depends on what you are moving and why.

Polygon PoS runs its own validators and its own native asset, and uses Ethereum's address format and developer tools. Fees are tiny and paid in POL, which replaced MATIC as the network's native token.

Most people meet it as a withdrawal option on an exchange, chosen because it is cheap. That is a reasonable reason, as long as the wallet or platform on the other end also supports it.

Tron addresses start with T, which makes them easy to tell apart from everything else on this page — a rare mercy. It carries a very large share of real-world USDT transfers, particularly for cross-border payments, because it is fast and, under the right conditions, almost free.

"Under the right conditions" is the part to understand. Tron does not charge a simple fee. It gives every account a small daily allowance of bandwidth, and transfers that touch a token contract also consume energy. You obtain energy by freezing TRX, and if you have none frozen the network burns TRX instead — which is why the same USDT transfer costs one person nothing and another several dollars. Exchanges handle this for you; a self-custody wallet with no TRX in it will not.

Keep a small amount of TRX in any Tron wallet you intend to send from. Holding USDT with a zero TRX balance is the Tron version of holding USDC with no ETH.

Solana uses neither the 0x format nor a fixed prefix — addresses are Base58 strings that begin with any character, which makes them visually distinct from Ethereum-style addresses but harder to eyeball for typos.

Slots come roughly every 400 milliseconds and transactions reach finality in about 12.8 seconds. A consensus upgrade called Alpenglow, targeting around 150 milliseconds, has been in development with activation expected in the second half of 2026; it is not live at the date below, so treat any article describing it in the present tense with care.

One practical quirk: holding a token on Solana requires a token account, and creating one costs a small refundable deposit in SOL. As with every other network here, keep a little of the native asset in the wallet or you will be unable to move anything.