How can users protect their cards using disposable virtual numbers?

[Student]

Single-use virtual card numbers are a powerful tool for protecting financial data when making online purchases, especially in the face of rising cyber threats. They help minimize the risks of fraud, data leakage, and unauthorized use of your primary card. In this answer, I will explain in detail what single-use virtual cards are, how they work, how to use them, their advantages and disadvantages, and will focus on foreign banks and services that offer this service. For educational purposes, I will also discuss technical aspects, use cases, security measures, and potential limitations.

What are one-time virtual card numbers?​

A virtual card is a digital version of a bank card, existing only in electronic form without a physical card. It includes:

• Unique 16-digit card number.
• CVV/CVC code (usually three digits).
• Duration of validity (often limited, such as a few hours or days).

Single-use virtual cards are designed to be used for a single transaction or for a short period of time (e.g., 24 hours). Once the transaction is completed or the card expires, it becomes inactive, making it useless for further use. These cards are linked to a primary bank account or e-wallet, but the primary card details remain hidden from the merchant, providing an additional layer of security.

How do disposable virtual cards work?​

1. Creating a card:
   • The user requests the creation of a virtual card through a mobile application or web interface of the bank/service.
   • The system generates a temporary card number, CVV code, and expiration date, which can be customized (e.g., for a single transaction or with an amount limit).
   • The user can specify a maximum transaction amount (for example, $50) or make the card a one-time use card.
2. Payment usage:
   • When making a purchase in an online store, the user enters the details of the virtual card instead of the main one.
   • The payment system (Visa, Mastercard, etc.) checks the card details and debits funds from the main account without disclosing its details.
3. Deactivation:
   • After a successful transaction, the disposable card automatically becomes inactive.
   • If the card is not a one-time use card, the user can manually delete it through the application.
   • If a transaction is declined (for example, due to a store error), the card can be reused within the established limit or expiration date, depending on the service settings.
4. Technical safety:
   • Virtual cards use the same encryption protocols as physical cards (e.g. payment tokenization).
   • The virtual card details are not directly linked to the main card, which reduces the risk of the main account being compromised.
   • Many services integrate two-factor authentication (2FA) for creating and using cards.

Banks and services offering one-time virtual cards​

Many foreign banks and fintech companies offer virtual card services, including disposable ones. Here's a detailed overview of popular platforms, their capabilities, and features:

1. Revolut (Europe, USA, Australia, etc.)​

• Description: Revolut is a UK-based global fintech platform that offers virtual cards as part of its banking services.
• Functionality of virtual cards:
  • Create one-time virtual cards for every transaction through the Revolut app.
  • Automatic deactivation of the card after use.
  • The ability to set limits on the amount and category of expenses (for example, only for online purchases).
  • Support for integration with Apple Pay and Google Pay.
• How to use:
  1. Download the Revolut app and register.
  2. In the Cards section, select Create a virtual card and check the Disposable option.
  3. Set a limit (e.g. €50) and get your card details.
  4. Use the card to pay, after which it will be automatically deactivated.
• Advantages:
  • High level of security thanks to single-use cards.
  • Instant card creation with no fees on standard plans.
  • Supports multiple currencies, making it convenient for international purchases.
• Limitations:
  • Availability may vary by region (for example, Revolut is limited in some Asian countries).
  • Some features (such as a larger number of virtual cards) are only available on paid plans (Revolut Plus, Premium, Metal).
• Note: Revolut uses tokenization for additional security and also offers real-time transaction notifications.

2. Privacy.com (USA)​

• Description: Privacy.com is a US-based service that creates virtual cards for secure online shopping.
• Functionality of virtual cards:
  • Creation of single-use cards for each transaction.
  • The ability to create merchant-locked cards that work only with the selected merchant.
  • Setting limits on the amount and frequency of transactions.
  • Pause or remove a card at any time.
• How to use:
  1. Register at Privacy.com and link your bank account or debit card.
  2. In the interface, select “Create a New Card” and configure the parameters (one-time card or for a specific store).
  3. Get your card details and use them for payment.
  4. After the transaction, the disposable card is deactivated.
• Advantages:
  • High level of control: you can set limits and block cards for specific merchants.
  • Free basic plan with the ability to create up to 12 cards per month.
  • Convenient for subscriptions: you can pause your card to avoid automatic charges.
• Limitations:
  • Only available to US residents with a US bank account.
  • Limited number of cards on the free plan (paid Pro plan removes restrictions).
• Note: Privacy.com integrates with popular browsers via plugins, making it easier to enter your card details.

3. PayPal Key (global, with regional restrictions)​

• Description: PayPal Key is a virtual card from PayPal that lets you make purchases without revealing your main card or PayPal account information.
• Functionality of virtual cards:
  • Generate a virtual card number linked to your PayPal account.
  • Can be used for one-time transactions (although PayPal Key is more often used as a reusable card).
  • Support for all stores that accept Mastercard.
• How to use:
  1. Sign in to your PayPal account and activate PayPal Key (availability varies by region).
  2. Get your virtual card number, expiration date and CVV.
  3. Use your card to pay in online stores.
  4. After use, you can delete the card or create a new one.
• Advantages:
  • Integration with an existing PayPal account, which is convenient for platform users.
  • High level of security thanks to PayPal's reputation.
  • Support at most online stores that accept Mastercard.
• Limitations:
  • PayPal Key is not available in all countries (for example, limited in some regions of Europe).
  • It doesn't always support single-use cards in the full sense of the word—more often, these are reusable virtual cards.
• Note: PayPal Key requires identity verification and linking a bank account or card.

4. Wise (formerly TransferWise, globally)​

• Description: Wise is an international financial platform offering multi-currency accounts and virtual cards.
• Functionality of virtual cards:
  • Create up to three virtual cards linked to your Wise account.
  • Possibility to set up one-time or temporary cards with limits.
  • Multiple currency support, ideal for international purchases.
• How to use:
  1. Open a Wise account and download the app.
  2. In the Cards section, select Create a virtual card.
  3. Set up your options (e.g. one-time use card with $100 limit).
  4. Use card details for payment.
• Advantages:
  • Convenient for users making purchases in different currencies.
  • Transparent fees and exchange rates.
  • Quickly create and delete cards.
• Limitations:
  • Limit on the number of virtual cards (up to three on the free plan).
  • Single-use cards may not be available in some regions.
• Note: Wise integrates with Apple Pay and Google Pay, making it easier to use cards.

5. Monzo (UK, USA)​

• Description: Monzo is a British digital bank, also available in the US. It is known for its user-friendly interface and security features.
• Functionality of virtual cards:
  • Creation of virtual cards for online purchases with one-time use.
  • Integration with Apple Pay and Google Pay.
  • Ability to freeze or delete cards at any time.
• How to use:
  1. Install the Monzo app and open an account.
  2. In the Cards section, select Add a virtual card.
  3. Set up your options (eg single use card with a £50 limit).
  4. Use the card for payment and delete it after use.
• Advantages:
  • Simple and intuitive interface.
  • Instant transaction notifications.
  • High level of security thanks to tokenization.
• Limitations:
  • Available in UK and US only.
  • Some features require a paid plan (Monzo Plus or Premium).
• Note: Monzo offers spending analytics to help you track your virtual card usage.

6. N26 (Europe)​

• Description: N26 is a German digital bank popular in the EU countries.
• Functionality of virtual cards:
  • Create virtual cards for secure online purchases.
  • Possibility to set up disposable or temporary cards.
  • Integration with Google Pay and Apple Pay.
• How to use:
  1. Register with N26 and download the app.
  2. In the Cards section, select Create a virtual card.
  3. Set limits and use the card to pay.
• Advantages:
  • Quick card creation without additional fees.
  • Convenient for EU residents.
  • Multiple currency support.
• Limitations:
  • Limited availability outside Europe.
  • Disposable cards may not be available on the basic plan.
• Note: N26 actively uses 2FA to enhance security.

How can users use disposable virtual cards?​

Step 1: Select a service​

Select a bank or service available in your region. For example:

• For the US: Privacy.com or Monzo.
• For Europe: Revolut, N26, Wise.
• For global use: PayPal Key (where available).

Step 2: Create a virtual card​

1. Install the bank/service app or log in to the website.
2. Find the "Virtual Cards" or "Create a Card" section.
3. Select the card type (single-use or reusable) and configure the settings:
   • Amount limit (e.g. $50 or €100).
   • Validity period (e.g. 1 day or until the first transaction).
4. Confirm card creation (2FA may be required, such as an SMS code or biometrics).
5. Get card details: number, CVV, expiration date.

Step 3: Using the Card​

1. When paying in the online store, select the card payment method.
2. Enter your virtual card details.
3. Confirm the payment (for example, via 3D-Secure with an SMS code).
4. After the transaction, the single-use card is deactivated automatically, but the reusable card can be deleted manually.

Step 4: Monitoring and Control​

• Please check your bank statement to ensure the transaction went through correctly.
• Set up transaction notifications in the app.
• Remove unused cards to avoid accidental reuse.

Advantages of disposable virtual cards​

1. Fraud protection:
   • If the card details are leaked (for example, if the store is hacked), they are useless, as the card is deactivated after use.
   • The main account remains protected since the virtual card details are not directly linked to it.
2. Expense control:
   • The user can set a precise limit on the transaction amount, which eliminates the risk of being charged a larger amount.
   • This is useful for trial subscriptions where the store can automatically charge you.
3. Privacy:
   • The merchant does not receive the primary card details, which reduces the risk of compromise.
   • Some services (such as Privacy.com) allow you to create cards linked to specific stores.
4. Flexibility:
   • Virtual cards can be created instantly and in any quantity (depending on the service).
   • Support for Apple Pay and Google Pay integration makes it easy to use.
5. Simplicity:
   • Creating and managing cards takes just a few minutes via a mobile app.
   • Real-time transaction notifications help you keep track of your spending.

Disadvantages and limitations​

1. Limited availability:
   • Some services (such as Privacy.com) are only available in the United States.
   • PayPal Key is regionally restricted, and Revolut may not work in some countries in Asia or Africa.
2. Usage restrictions:
   • Single-use cards are not suitable for recurring payments (such as Netflix subscriptions) as they are deactivated after the first transaction.
   • Some stores may reject virtual cards due to their temporary nature.
3. Service dependency:
   • If the bank/service's app or website is unavailable (for example, due to a technical failure), it is impossible to create a new card.
   • Some features may only be available on paid plans.
4. Problems with returns:
   • If the store processes a return and the virtual card has already been deactivated, the return process may be more complicated, as the funds must be credited to the main account.
5. Commissions:
   • Some services may charge a fee for issuing virtual cards or for additional features (for example, Revolut limits the number of cards on its free plan).

Practical tips for safe use​

1. Use on unverified sites:
   • Create disposable cards for purchases on new or suspicious websites.
   • Check whether the site uses HTTPS and read reviews about the store.
2. Set minimum limits:
   • Set the limit close to the purchase price to minimize losses in case of an error.
3. Enable two-factor authentication:
   • Make sure your bank or service account is protected by 2FA (e.g. SMS code, biometrics).
4. Transaction monitoring:
   • Set up transaction notifications in the app.
   • Check your bank statements regularly.
5. Remove unused cards:
   • If the card is not disposable, remove it after use to avoid accidental reuse.
6. Check the reliability of the service:
   • Check reviews and security policies of third-party platforms (such as Privacy.com or Revolut).
   • Avoid suspicious services that may collect your data.
7. Use for trial subscriptions:
   • Create disposable cards for registration on services with a free trial period to avoid automatic charges.
8. Update your app:
   • Make sure your bank or service app is updated to the latest version to address any vulnerabilities.

Real-life use cases​

1. Purchase on an unfamiliar website:
   • You want to buy electronics on a new marketplace. You use Revolut to create a one-time card with a $100 limit. After payment, the card is deactivated, protecting your main account.
2. Trial subscription period:
   • You sign up for a streaming service with a free trial. You create a one-time use card through Privacy.com to avoid charges after the trial ends.
3. International purchases:
   • You book a hotel through an international website using a virtual Wise card in the desired currency (e.g., EUR). This protects your primary card details.
4. Expense control:
   • You use Monzo to create a virtual card with a £50 limit for purchases at a specific store, so you don't go over your budget.

Technical aspects of security​

1. Tokenization:
   • Most banks (e.g. Revolut, N26) use tokenization, replacing real card data with unique tokens for each transaction.
   • This reduces the risk of data interception during transmission.
2. 3D-Secure:
   • 3D-Secure (such as Verified by Visa or Mastercard SecureCode) is often used to confirm transactions, requiring an SMS code or biometric authentication.
3. Encryption:
   • Virtual card data is protected by encryption standards (e.g. AES-256) used by banks and payment systems.
4. Access restriction:
   • Virtual cards often have restrictions on transaction types (e.g., online only) and geography, which reduces the risk of using them in offline stores.

Potential risks and how to avoid them​

1. Phishing and fake services:
   • Fraudsters may create fake websites posing as Revolut or Privacy.com.
   • Solution: Download apps only from the App Store or Google Play, check website URLs (e.g. revolut.com).
2. Data leak in the store:
   • Even with a virtual card, your purchase details can be compromised if the store is untrustworthy.
   • Solution: Use trusted platforms and check reviews.
3. Technical failures:
   • Payments may be declined due to service errors.
   • Solution: Create backup virtual cards or have an alternative payment method.
4. Regional restrictions:
   • Some services (such as Privacy.com) are not available outside the United States.
   • Solution: Use global platforms like Revolut or Wise.

Conclusion​

Single-use virtual card numbers are an effective way to protect your finances when shopping online. International banks and services such as Revolut, Privacy.com, PayPal Key, Wise, Monzo, and N26 offer convenient and secure solutions for creating such cards. They provide fraud protection, data privacy, and spending control. For maximum security, it's important to use two-factor authentication, set limits, monitor transactions, and choose trusted platforms.