You are about to top up a crypto card with USDT, and the deposit screen asks one question before it will show you an address: which network? TRC-20, ERC-20, BEP-20, maybe a handful more. It looks like a technicality. It is not. That single choice decides how much of your money the blockchain eats on the way in, how long you wait for the balance to show up, and — if you get it wrong — whether the money arrives at all.
Here is the short answer, then the reasoning. For everyday top-ups, send USDT on TRC-20. It is cheap, it is fast, and it is what the deposit is expecting nine times out of ten. Everything below is when and why to deviate.
What these networks actually are
USDT is not one thing living in one place. Tether issues the same dollar-pegged token on many blockchains, and the "network" you pick is just which chain's copy you are moving. Same face value, different rails underneath. Tether keeps a running list of the chains it supports on its supported protocols page, and the three you will meet on almost every deposit screen are these.
TRC-20 is USDT on the Tron blockchain. Tron was built cheap and fast, and stablecoin transfers are the thing it does best. This is why exchanges, OTC desks and most card issuers treat TRC-20 as the default USDT rail.
ERC-20 is USDT on Ethereum — the original, the most battle-tested, and the most expensive to move. Ethereum charges gas for every transaction, and that gas is priced by how busy the network is. When the network is quiet it is fine. When it is not, it stings.
BEP-20 is USDT on BNB Chain, Binance's network. It behaves a lot like Tron: low fees, quick blocks. It is common if you pulled funds off Binance or use wallets that default to BNB Chain.
The token buys the same coffee no matter which of these it rode in on. What differs is the toll booth on the way there.
Fees and speed, compared
Numbers first, then the caveat that matters more than the numbers. These are network fees — what the chain charges to move your USDT — as of mid-2026. They are not the card's top-up fee, which is separate and covered below.
| Network | Typical transfer fee | Confirmation | Best when |
|---|---|---|---|
| TRC-20 (Tron) | ~$1–3, near-zero with energy | ~1–2 min | Small or frequent top-ups |
| BEP-20 (BNB Chain) | ~$0.05–0.30 | Under ~1 min | Funds already on BNB Chain |
| ERC-20 (Ethereum) | ~$0.50–7, spikes past $30 when busy | Seconds to several min | USDT already on Ethereum |
Now the caveat: these are ranges, not promises. Chain fees float. Tron changed its energy pricing in August 2025, which is why a TRC-20 transfer that once cost pennies can run a dollar or two if your wallet holds no energy — still trivial, but not literally free anymore. Ethereum gas is the wild one. Anyone quoting you an exact "ERC-20 costs $X" is guessing; it depends entirely on network load at the second you hit send. Treat the table as orders of magnitude, not a receipt.
The takeaway is blunt. On a $200 top-up, an ERC-20 gas spike can quietly cost more than the card's issuance fee. On TRC-20 or BEP-20 that same transfer is a rounding error. For a related walkthrough of the whole funding-to-spending flow, the guide on how to spend USDT online picks up where this one leaves off.
Which networks ExCards supports
A comparison only helps if the card actually credits the chain you pick. ExCards accepts top-ups on all three of the networks above — ERC-20, TRC-20 and BEP-20 — plus Bitcoin, Polygon, Arbitrum, Optimism and Avalanche.
Two things are worth pinning down about that list. First, no matter which network you send on, the balance lands in USDT. Send Bitcoin and it is sold to USDT the instant the deposit confirms; send ETH on Arbitrum and same story. The card holds dollars-in-USDT, not whatever coin you shipped. Second, the Layer-2 options — Polygon, Arbitrum, Optimism — are genuinely cheap alternatives if your assets already live there, so you are not forced onto Tron just to keep fees down.
One number that does not move with the network: the top-up fee. ExCards charges a flat 3.5% on the deposited amount whether you use TRC-20, ERC-20 or anything else on the list. The mandatory first top-up is 10 USDT, and that goes straight to your spendable balance rather than getting pocketed as a fee. The full network list and the mechanics live on the USDT card page and the Tether card page.
How to actually pick
Skip the ideology. The right network is a two-step decision, and it takes about ten seconds.
- Where does your USDT already live? On an exchange, check which withdrawal network is cheapest — usually TRC-20. In a wallet, use whatever chain the funds are on so you avoid a bridge. Bridging to "the cheap chain" often costs more than the fee you were trying to dodge.
- How big and how often? Small, regular top-ups favor TRC-20 or BEP-20 every time. One large infrequent deposit? The network fee barely matters as a percentage, so send on whatever is convenient — even ERC-20 if that is where the money is.
Put simply: default to TRC-20, deviate only to avoid a bridge. A crypto nomad paying for AI subscriptions and SaaS in $20–100 chunks should basically always be on Tron. Someone consolidating a $10,000 balance from an Ethereum wallet once a quarter can send ERC-20 and not think twice — the gas is noise against the size of the transfer.
And do not over-optimize. Saving forty cents on a chain fee is not worth an hour of bridging and three extra transactions, each with its own fee and its own chance to fat-finger an address.
Mistakes that actually lose funds
Fees are the boring risk. These are the ones that cost people their whole deposit.
Wrong network, right-looking address. ERC-20 and BEP-20 use the same address format — a 0x... string. It is entirely possible to copy your Ethereum deposit address and accidentally send on BNB Chain, or vice versa. Where the destination cannot see the funds, recovery ranges from a slow support process to flatly impossible. The habit that saves you: always copy the address fresh from the deposit screen for the exact network you chose, and never reuse an address from a different chain.
Sending on an unsupported chain. Your wallet may offer to send USDT over a network the card does not credit. If you do, the transfer is valid on-chain but invisible to the card — the money is somewhere, just not on your balance. Stick to the supported list every single time.
Ignoring a memo where one is required. TRC-20, ERC-20 and BEP-20 do not use memos, so this will not bite you there. But some chains — TON, XRP, certain exchange transfers — require a memo or destination tag. Miss it and the funds hit a shared address, turning a two-minute top-up into a support ticket. If the deposit screen shows a memo field, it is not optional.
Sending below the minimum. Dust a deposit under the accepted threshold and it may not credit, while the network fee is gone regardless. Check the minimum before you send, especially on a first top-up.
None of these are exotic. They are the same four errors, repeated, in every "help I lost my USDT" thread on Reddit. Slow down for the ten seconds it takes to match the network, and none of them can happen to you.
The bottom line
Networks are plumbing. TRC-20 is the cheap, fast default and should carry most of your top-ups. BEP-20 is its equal when your funds already sit on BNB Chain. ERC-20 earns its keep only when moving off Ethereum would cost more than just paying the gas. The card holds USDT at the end either way, and the 3.5% top-up fee is the same across all of them — so the network choice is purely about the blockchain toll and not losing the deposit.
If you want the wider context — how the balance converts to a Visa or Mastercard payment, limits, KYC — the complete USDT card guide is the pillar to read next, and the FAQ handles the operational odds and ends. When you are ready to fund one, pick TRC-20, send the exact amount to the exact address, and you are spending in minutes.
Frequently asked questions
What is the cheapest network to fund a crypto card with USDT?
For most people, TRC-20 (Tron). A USDT transfer on Tron usually costs a dollar or two after the August 2025 energy price change — and close to nothing if your wallet already holds energy. BEP-20 (BNB Chain) is comparably cheap, often a few cents. ERC-20 (Ethereum) is the expensive one, so avoid it unless your USDT already lives on Ethereum and moving it elsewhere would cost more than sending it as-is.
Is TRC-20 always the best choice?
No. TRC-20 is the default for small and frequent top-ups because it is cheap and fast. But the real rule is to match the network to where your USDT already sits. If your funds are on BNB Chain, send BEP-20 and skip a bridge. If they are on Ethereum and bridging would cost more than the gas, just send ERC-20 once. The goal is to move your money onto the card with the least total cost, not to worship one chain.
What happens if I send USDT on the wrong network?
This is the number one way people lose a top-up. If you send USDT over a chain the card does not credit, the deposit will not appear on your balance, and recovery ranges from slow to impossible depending on the chains involved. Always copy the deposit address for the exact network shown in the dashboard, and send on that network only. Never reuse an address from a different chain.
Does the top-up fee change depending on the network?
The card's top-up fee and the network fee are two separate things. ExCards charges a flat 3.5% top-up fee on the deposited amount regardless of which network you use — TRC-20, ERC-20 or BEP-20, the percentage is the same. The network fee is what the blockchain itself charges to move your USDT, and that is where TRC-20 and BEP-20 beat ERC-20.
How long does a USDT deposit take to credit?
It depends on how fast the chain confirms, not on the card. TRC-20 and BEP-20 usually confirm within a minute or two. ERC-20 is normally quick but can drag when Ethereum is congested. Crediting cannot happen before the network agrees the transfer is final, so budget for confirmation time on larger sends and do not panic if a busy block takes a few minutes.
Do I need a memo or destination tag to fund the card?
Not for TRC-20, ERC-20 or BEP-20 — those use a plain address with no memo. Memos and destination tags belong to networks like TON, XRP and some exchange-internal transfers. If the deposit screen shows a memo field, fill it in exactly; a missing memo on a memo-required chain sends funds to a shared address and turns crediting into a support ticket.
Which networks does ExCards support for top-ups?
ExCards accepts top-ups on ERC-20, TRC-20 and BEP-20, plus Bitcoin, Polygon, Arbitrum, Optimism and Avalanche. Whatever you send lands on your balance as USDT after the 3.5% top-up fee. The mandatory first top-up is 10 USDT, credited straight to your balance rather than taken as a fee. The USDT card page lists the current supported networks.
Can I fund the card with something other than USDT?
Yes. You can top up with Bitcoin and assets on the supported networks, but the balance is held in USDT, not in whatever you sent. Send BTC or ETH and you are effectively selling it for USDT the moment the deposit confirms. If you want to hold your position in a volatile coin, do that in your own wallet and only move USDT to the card when you are ready to spend.