A USDT card is a Visa or Mastercard whose balance lives in Tether instead of a bank account. You move USDT to a deposit address. The issuer credits the card. You spend at any merchant on the network and the merchant sees a plain card transaction in USD or local currency.

That is the entire story at the mechanism level. Everything else — networks, fees, KYC, tier choice, depeg risk — is detail. This guide walks through the detail in the order you actually hit it.

The foundational explainer on how crypto cards work is in our What is a crypto card piece. This one zooms in on USDT specifically: why it became the default funding asset, which network to send on, what it really costs, what breaks, and how to pick between the two ExCards tiers.

Why USDT ended up as the default

Three reasons. Liquidity, network reach, and the failures of the alternatives.

Liquidity first. USDT is the most-traded asset in crypto by a wide margin. On any major exchange you can move six figures in and out of USDT in seconds with under 5 basis points of slippage. Card issuers care about this because they hedge cardholder balances back to USD and need predictable conversion at authorization. USDC is a close second; the rest are not in the same liquidity tier.

Network reach is the practical reason a regular user funds in USDT instead of USDC. Tether issues on TRC-20, ERC-20, BEP-20, Polygon, Arbitrum, Optimism, Avalanche and Solana, among others. TRC-20 transfer fees run under a dollar. USDC on Ethereum costs more in gas, and its cheap-network coverage is narrower in practice. Paying $15 of gas to move $200 of USDC makes no sense when TRC-20 USDT lands for cents.

Then the alternatives. UST collapsed in May 2022 and wiped out the "algorithmic" stablecoin category. USDC depegged briefly during the Silicon Valley Bank weekend in March 2023, recovered, and ceded some default-asset status to USDT in the process. DAI works but liquidity is thinner and most card issuers do not list it. FDUSD and PYUSD have not crossed the universal-wallet-support threshold. USDT did. That network effect is why it sits at the top of every funding dropdown.

USDT is not risk-free. Tether publishes quarterly attestations showing reserves composed largely of US Treasuries and cash equivalents — attestations, not full GAAP audits. For spending USDT on a card, where the balance is short-lived between top-up and use, this is a workable default.

The networks: TRC-20, ERC-20, BEP-20, Polygon and the rest

You can fund an ExCards card with USDT on any of the eight supported networks. Practical differences below.

Network Typical fee Speed When it makes sense
TRC-20 (Tron) $0.50 - $1.50 ~1 min Default choice. Cheap, fast, deepest liquidity on exchanges.
ERC-20 (Ethereum) $2 - $20 2 - 5 min Funds already on Ethereum and you do not want to bridge.
BEP-20 (BNB Chain) $0.10 - $0.40 ~30 sec Cheap. Common on Binance withdrawals.
Polygon $0.01 - $0.10 ~10 sec Cheapest. Good if your funds are on Polygon already.
Arbitrum / Optimism $0.10 - $0.50 ~5 sec Cheap L2s. Less common as USDT route.
Avalanche $0.50 - $2 ~5 sec Niche. Fine if that is where your USDT lives.
Bitcoin (Omni / Lightning) varies varies Rare. Most issuers no longer support Omni.

TRC-20 is the default for a reason. If you have no specific reason to pick another network, send TRC-20. The one thing to verify: the deposit address you copied from the ExCards dashboard is a TRC-20 address, not ERC-20. Sending USDT to a wrong-network address is the single most common way people lose funds in this category. There is no automatic recovery. Always copy-paste, never type, and verify the first and last four characters before signing.

When withdrawing from Binance, OKX, Bybit or Kraken, the network selector often defaults to ERC-20. Change it to TRC-20 before confirming. The exchange withdrawal fee is also lower — Binance charges 1 USDT on TRC-20 versus 5-25 USDT on ERC-20 depending on gas.

How a top-up actually flows

Six steps, 1 to 5 minutes depending on network.

  1. Open the app. Web at app.excards.io or the Telegram mini-app. Go to your card, hit Top up, select USDT and the network.
  2. Copy the deposit address. Fresh address per top-up. Verify the first and last four characters against what you paste into your exchange or wallet.
  3. Send USDT. Match the network exactly. TRC-20 to TRC-20. ERC-20 to ERC-20.
  4. Wait for confirmations. TRC-20: 30-90 seconds. ERC-20: 2-5 minutes. BEP-20: ~30 seconds. The dashboard updates when the deposit lands.
  5. Top-up fee applied. 3.5% of gross deposit. Send $200, credited roughly $193.
  6. Balance is live. Spendable immediately on any Visa or Mastercard merchant.

Missing deposits after the expected window usually mean a wrong-network send. Contact app.excards.io with the transaction hash. Recovery on same-chain mismatches is sometimes possible. Cross-chain mismatches are not recoverable.

Real fees, not the sticker price

The sticker fees on a USDT card are simple. Real cost per dollar spent depends on how you use it. Walk-through using the actual ExCards numbers from the fees page.

Issuance. $35 once for the Visa E-commerce, $50 once for the Mastercard Business.

Mandatory first top-up. $10 USDT, credited to balance. Not a fee — it is your starting balance.

Top-up fee. 3.5% of every deposit. Send $1,000, credited $965. Dominant cost. No volume discount.

Authorization fee.

  • Visa E-commerce: tiered. $0.10 on auths under $1, free on $1 and above. Plus $0.03 per 3D-Secure challenge.
  • Mastercard Business: flat. $0.50 per authorization regardless of amount.

The two models cross break-even around the $100 transaction range. If your spend is dominated by sub-dollar tests and small SaaS subs, the Visa is cheaper. For a few large monthly charges and the Visa's $20K-per-tx ceiling becomes the bottleneck before the auth fee does, the Mastercard wins.

FX margin. Visa and Mastercard apply a wholesale FX rate to non-USD merchants, typically 0.2% to 1% over mid-market. ExCards does not stack additional FX margin on top of the network rate. EU hotels and non-USD subscriptions pay this; US-billed services do not.

High-decline penalty. Visa tier only. $0.80 per declined authorization if your decline rate crosses 10% over a sliding window. Most users never hit it. Media buyers running aggressive split-tests sometimes do.

A concrete monthly example. A freelancer pays OpenAI ($60), Anthropic ($20), ChatGPT Plus ($20), AWS ($180), a small Meta Ads run ($800), GitHub ($21), Cloudflare ($60), and books a $400 hotel in EUR. Total spend $1,561. One top-up of $1,650 at 3.5% costs $57.75. Eight authorizations all over $1, zero auth fees on the Visa tier. The hotel triggers ~$3 of FX margin. Total card cost on the Visa: $60.75 on $1,561 of spend, or 3.9%. The 3.5% top-up dominates.

Same scenario on the Mastercard: $57.75 top-up + $4 in auth fees + $3 FX = $64.75, or 4.1%. The Visa is cheaper at this volume because the spend is not large enough to amortize the higher card price or to make the flat auth fee pay off. Cross over to $5K-$10K months and the Mastercard tends to win — especially when a few transactions exceed the Visa's $20K per-tx ceiling.

Where USDT cards actually get used

The funding source does not matter to merchants. The card works wherever Visa or Mastercard does — roughly 200 countries, tens of millions of merchants. Heaviest practical categories:

  • AI services — OpenAI, Anthropic, Google AI, Mistral, Perplexity, Replicate, Hugging Face. Many decline cards from countries where US-facing processors flag local BINs. A USDT-funded US-friendly BIN clears the filter.
  • Ad platforms — Meta, Google, TikTok, X, LinkedIn. Media buyers with international clients centralize billing in USDT and skip the local bank's FX leg.
  • SaaS and infrastructure — AWS, Vercel, Cloudflare, GitHub, Linear, Notion, Figma. Standard auto-pay works.
  • Subscriptions — Spotify, Netflix, YouTube Premium, Apple One, ChatGPT Plus, Claude Pro.
  • E-commerce — Amazon, AliExpress, Shopify stores, Steam, marketplaces. A few regulated categories (alcohol delivery, certain electronics resellers) decline prepaid BINs — rare but worth knowing.
  • Travel — flights direct, hotels via Booking, transit. The Mastercard Business handles airport lounges and rental-car deposits the Visa E-commerce cannot.
  • Apple Pay and contactless — Mastercard Business only. Full breakdown in our Apple Pay and Google Pay article.

What does not work: OFAC, EU and UK sanctioned countries, the small set of merchants that ban prepaid BINs outright, and high-risk merchant categories at most BIN sponsors (some gambling, some adult, some peer-to-peer money apps). Current rules in the geo policy.

USDT vs USDC vs DAI vs FDUSD on cards

Most issuers — ExCards included — denominate the card balance in USDT regardless of what stablecoin you deposited. So the question is less "which stablecoin on the card" and more "which stablecoin do I send to top up."

USDT wins on cost and network coverage. TRC-20 transfers are cheaper than any other major stablecoin route. If your funds are already in USDT, send USDT and stop optimizing.

USDC is the natural choice if you hold USDC and your exchange charges a fee to swap. Most exchanges support USDC withdrawals on Polygon, Arbitrum and Optimism. The card credits in USDT-equivalent and may include a small swap spread.

DAI runs a different reserve mechanism (over-collateralized crypto, not bank reserves). Liquidity is thinner. Most card issuers either do not list it or apply a wider swap spread. Fine for small amounts.

FDUSD is newer, mostly liquid on Binance. PYUSD is PayPal's, and most card issuers have not integrated it. Both workable in 2026, neither the default.

If you want to actually hold a non-USDT stablecoin on the card, ask the issuer directly. ExCards converts to USDT at deposit. Most competitors do the same.

Risks specific to USDT cards

Risks split across three actors: Tether, the card issuer, and the network rules set by Visa and Mastercard. AML and sanctions enforcement on stablecoin rails is guided by the Financial Action Task Force, which sets the baseline most issuers operate inside.

Tether reserve risk. Reserves are attested quarterly, not full-audited in the GAAP sense. Published composition is mostly US Treasuries and cash equivalents — a more conservative mix than the 2020-2021 commercial-paper-heavy version. Tail risk: regulatory action or reserve shortfall that breaks the peg materially. Historical depegs (October 2018 down to ~$0.94, May 2022 to ~$0.95) recovered within days. Mitigation for cardholders: keep balances small and top up close to spend.

Issuer and BIN sponsor risk. The card balance sits with the program manager and is denominated in USDT. If the issuer or BIN sponsor faces enforcement — sanctions screening failures, AML weakness, sponsor bank winding down — cards can freeze. Not unique to USDT cards; applies to every prepaid program. Mitigation: read the AML, KYC, geo and risk pages of any issuer before funding. If not published, walk. Ours are at AML, KYC, geo and risk.

BIN program risk. Visa and Mastercard occasionally revise rules for crypto-funded programs. Past changes: tighter sanctions screening, mandatory 3DS on certain merchant categories, restrictions on specific high-risk merchant types. These flow through as occasional declines, not balance loss. A card that worked at merchant X last quarter may not this quarter if X moved to a flagged category.

Wrong-network sends. Not USDT-specific but the most common loss mode. TRC-20 and ERC-20 addresses look similar at a glance. Match the network, verify first and last four characters, and start with a small test deposit on first use.

Tax disposal. Most jurisdictions treat spending crypto as a taxable disposal. USDT being a stablecoin does not exempt you — the disposal is still an event, even when gain or loss is near zero. Track top-up amounts and spend records. The card does not change tax exposure; it changes the payment rail.

Visa E-commerce vs Mastercard Business: how to pick

Two tiers, different purposes. The full table is on the product page; the short version below.

Visa E-commerce — $35. Online-only. $20,000 per transaction. No daily or monthly cap. Tiered auth fee: $0.10 under $1, free above. $0.03 per 3DS challenge. No Apple Pay, no Google Pay, no offline POS. Optimized for: freelancers and small operators paying AI services, SaaS, ad platforms, e-commerce and subscriptions from a desktop checkout. The math is hard to beat if your spend pattern fits that profile.

Mastercard Business — $50. Online and offline. $250,000 per transaction. $500K daily, $1M monthly. Flat $0.50 per auth. Apple Pay and Google Pay supported. Optimized for: media buyers running large invoices, business operators paying both online and at physical merchants, travelers needing mobile-wallet provisioning, anyone who occasionally pushes a single transaction above the Visa's $20K ceiling.

Decision framework:

  • If your monthly spend is under $5K and lives entirely online, the Visa tier costs less in absolute terms ($35 + 3.5% top-up vs $50 + 3.5% top-up).
  • If you need Apple Pay or Google Pay, the Mastercard is your only option — the Visa does not provision.
  • If you regularly run individual charges between $20K and $250K, the Mastercard's per-transaction headroom is the deciding factor.
  • If you travel and want to pay at coffee shops, hotels with tap-to-pay, or contactless transit, the Mastercard is the answer.
  • If you are running a tail of small SaaS subs ($5-$20 each) and your largest charge is a $500 AWS bill, the Visa's free-above-$1 auth fee saves you a small but real amount versus the Mastercard's flat $0.50.

Most ExCards users with predictable online spend pick the Visa first, then add the Mastercard later if they need contactless or higher limits. The product page lays out both side by side with exact limits and fees.

How to actually start

  1. Open @ex_cards_bot on Telegram or app.excards.io.
  2. Sign up with email and phone.
  3. Submit a passport scan. Light KYC, reviewed in minutes — full breakdown in our light KYC explainer.
  4. Pick a tier — Visa E-commerce or Mastercard Business.
  5. Pay the issuance fee in USDT. TRC-20 if you have no preference.
  6. Make the mandatory $10 top-up — credited to balance, not a fee.
  7. Card number, expiry and CVV are live in the dashboard. Paste into a checkout or, on the Mastercard tier, provision into Apple Pay or Google Pay.

Most users finish signup to first transaction in under 15 minutes. The usual bottleneck is the KYC review queue at off-peak hours.

Closing notes

USDT cards are a plumbing fix. They solve a specific problem: paying USD-denominated services from a USDT balance without routing through a local bank that may decline the transaction, charge a 3% FX fee, or take three business days to settle. No problem, no need for the card.

If you do have the problem, the calculation is short. 3.5% top-up fee plus per-transaction friction, against whatever your current alternative costs in declined charges, FX spread, delays and time on the phone with a bank. Most users switch after one too many declined Meta Ads invoices.

The market is more mature in 2026 than three years ago. Sponsor-bank enforcement has shaken out the unverified-card operators. Remaining issuers compete on fees, limits, KYC friction and supported jurisdictions. Pick one whose policies you can actually read, fund on TRC-20, top up close to when you spend, and treat the card balance like an exchange balance — not a savings account.

ExCards specifics: light KYC (passport scan, reviewed in minutes), two tiers at $35 and $50, 3.5% top-up across all networks, no monthly fees, USDT on eight networks. Limits and fees side by side on the USDT card landing and the product page. Operational questions in the FAQ. Start the issuance flow at app.excards.io.

Frequently asked questions

What is a USDT card?

A USDT card is a Visa or Mastercard whose balance is funded with Tether (USDT) instead of bank fiat. You send USDT to a deposit address controlled by the card issuer, the issuer credits the card balance, and from that moment forward the card behaves like any other Visa or Mastercard at any merchant on the network. Conversion to USD or local fiat happens at authorization. The merchant sees a normal card transaction.

Which USDT network should I use to top up?

TRC-20 if you want the cheapest fees — typically under $1 per transfer with one-minute finality. ERC-20 if the funds are already sitting on Ethereum and you do not want to bridge — fees range $2 to $20 depending on gas. BEP-20 is the middle ground on BNB Chain. Polygon and Arbitrum are fine if you already use them. The card balance ends up in USDT regardless of which network you sent on.

What does a USDT card actually cost to use?

Three line items. Issuance once — $35 for the ExCards Visa E-commerce, $50 for the Mastercard Business. Top-up fee on every deposit — 3.5% of the amount sent. Authorization fee per transaction — tiered on the Visa (free over $1, $0.10 under $1) or flat on the Mastercard ($0.50 per auth). No monthly fees on either tier.

Where do USDT cards work?

Anywhere on the Visa or Mastercard network — that is roughly 200 countries and tens of millions of merchants. The exceptions are jurisdictions under OFAC, EU or UK sanctions (Iran, North Korea, Syria, Cuba, listed Russian regions) and the small set of merchants that explicitly refuse prepaid BIN cards. Apple Pay, Google Pay and offline POS work on the Mastercard Business tier; the Visa E-commerce tier is online-only.

USDT vs USDC vs DAI — does the stablecoin matter for the card?

Not much, because the balance is denominated in USDT no matter what you deposited. If you send USDC or DAI, you are effectively swapping into USDT at the moment the deposit confirms — at whatever rate the issuer applies. USDT is the default funding choice because TRC-20 transfers are cheap and liquidity is deep on every exchange. If you hold USDC and your exchange charges a fee to swap, account for that in your top-up math.

Is a USDT card safer than holding USDT on an exchange?

Different risks, not strictly safer. Both rely on a third party to honor your balance. The card balance sits with the issuer and is denominated in USDT; an exchange balance sits with the exchange. The card lets you spend without moving funds back to a bank — which is the entire point — but you should treat the card balance the same way you treat an exchange balance: keep on it only what you plan to spend in the next few weeks.

What happens if USDT depegs while my balance is on the card?

Your balance is denominated in USDT, so a depeg event affects the spending power of that balance in USD terms. A 2% depeg means your $1,000 balance temporarily authorizes for roughly $980 of merchant charges. Historical depegs (October 2018, May 2022) recovered within days. If you are worried, do not pre-fund large amounts — top up closer to when you need to spend.

Should I get the Visa E-commerce or the Mastercard Business?

Visa E-commerce ($35) if you spend mostly on online services — AI subscriptions, SaaS, ad platforms, e-commerce — and you do not need Apple Pay or a per-transaction limit above $20,000. Mastercard Business ($50) if you need Apple Pay or Google Pay, plan to pay at physical terminals, run large single charges (up to $250K), or want the flat $0.50 auth fee for predictable cost on big transactions. Most media buyers and travelers pick the Mastercard. Most freelancers running OpenAI and a SaaS stack pick the Visa.