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3-D Secure (3DS)

3-D Secure (3DS) is a security check for online card payments that lets your card issuer confirm it is really you before approving the payment. When you buy crypto with a card, your issuer may ask you to enter a one-time passcode or use biometrics, such as a fingerprint, before the payment goes through.

How 3-D Secure works

3-D Secure is a card-industry standard, managed by EMVCo, that checks whether the person paying online is the real cardholder. The shop shares details about the payment and your device with your card issuer, the bank that gave you the card.

As of September 2026, EMVCo describes two paths:

  • Frictionless: the issuer approves a low-risk payment without asking you anything.
  • Challenge: for a higher-risk payment, the issuer asks you to prove it is you, for example with a one-time passcode or a fingerprint.

Visa calls its programme Visa Secure. Mastercard calls its programme Mastercard Identity Check.

Example

An illustrative case: you pay online with a debit card. Your bank opens a window and asks for a one-time code sent to your phone. You enter the code, the bank confirms it is you, and the payment continues.

Why it matters when you buy crypto

If you pay for crypto with a card, your card issuer may ask for a 3-D Secure check. Finish it in the window that opens, or the payment may not go through. If checks keep failing, see how to fix a failed 3DS authentication.

Card issuers may treat crypto purchases as cash advances, which can add a cash advance fee and interest. Coinmama does not add its own fee. All fees are shown before you confirm your order.

Payment options depend on your country: see supported payment methods before you buy crypto on Coinmama.

Risks and red flags

3-D Secure makes card fraud harder, but scammers imitate it.

  • A genuine check appears only during a payment you started. An unexpected code or approval request is a red flag.
  • Never share a one-time passcode with anyone who calls, texts or emails you, even if they claim to be from your bank or from Coinmama. Read about phishing attacks and employee impersonator scams.
  • Check the shop name and amount before you approve a payment.

Go deeper: our guide on how to buy crypto walks through a purchase step by step.

Related terms

  • Cash Advance Fee A cash advance fee is a charge a credit card issuer may add when it treats a payment as cash, which can include buying crypto.
  • Verification Verification, often called KYC (Know Your Customer), is the identity check a crypto provider carries out before you can buy.
  • Crypto Fees Explained: Spread, Card & Network Fees Crypto fees are the costs of buying, sending or swapping crypto, from processing fees and spreads to network fees paid to miners or validators.
  • Fiat On-Ramp A fiat on-ramp is a service that lets you exchange government-issued money, such as US dollars or euros, for cryptocurrency.
  • ACH Transfer (Automated Clearing House) An ACH transfer is an electronic payment between US bank or credit union accounts, sent in batches through the Automated Clearing House (ACH) Network.

Go deeper

Sources

  1. EMVCo: EMV 3-D Secure (accessed )
  2. Visa: Visa Secure (EMV 3-D Secure) (accessed )
  3. Mastercard Developers: Mastercard Identity Check (accessed )