The Hidden Risks of “Temporary Cards” Issued Before Physical Cards
Temporary card numbers issued for online payments are usually instantly assigned to digital wallets. However, the first few minutes of these cards are vulnerable to security breaches because some banks activate them without first verifying their use. Even if temporary cards are delivered on the same day, they may still be linked to the old card in the bank's systems. This means that even if the old card appears to be closed, some shopping systems may still recognize the temporary card as an “ongoing transaction.”
Some banks may delay assigning a CVV or PIN to temporary cards. This does not target the cardholder directly, but indirectly: fraudsters can more easily test cards that have been created with “incomplete information.”
Behavioral Threats Arising from the First Transactions Made with Temporary Cards
According to statistics, 12% of users who receive temporary cards in the US report an “unauthorized transaction” within the first 48 hours. This is because the card is activated quickly by the bank without considering user habits. Some digital wallet systems (such as Apple Pay and Google Wallet) can approve transactions on newly added cards without considering the user's address or device history. This makes transactions from fake devices appear more “natural.”
Cybersecurity firms report that temporary cards are often used for ‘testing’ on Amazon, eBay, and e-commerce platforms, with 3% of these tests being fraudulent. These tests typically involve a symbolic payment of $1.
Low-Profile Threats That Customer Service Doesn't Notice
Many banks assume that temporary cards have the same limits as physical cards only on their first use. However, some older infrastructures treat temporary cards as “new cards” rather than “renewed cards,” which creates gaps in transaction limits. Some temporary cards can block the balance for an extended period even if the transaction is not completed, such as when used for “pre-authorization” (e.g., a hotel reservation). 18% of users reported being unable to access their balance for weeks in such cases.
Most users believe that refunds made through temporary cards will not be returned to their account after the physical card arrives. However, the systems can automatically redirect these refunds to the user's account instead of the original temporary card.
Bank Policies Behind Temporary Cards
When issuing temporary cards, some banks may create a higher risk profile based on the cardholder's past fraud suspicions. This leads to the card being caught in the “risk filter” more often — some users are blocked before they can make any purchases with their temporary card. Transactions made with temporary cards are reviewed more frequently than those made with regular cards. In Canada and the United Kingdom, in particular, these types of cards are subject to more frequent “manual checks,” which can cause delays in purchases.
Some banks do not count transactions made with temporary cards as purchases that earn users points or promotions. This means that users who report lost cards may lose out on certain loyalty programs.
Covert Access Scenarios: How Are Temporary Cards Leaked?
Attackers attempt to access this information immediately after temporary cards are added to digital wallets using “timed attacks.” Attempts made as soon as an email notification is opened are the most risky. In some cases, temporary card information is combined with other information already in the hands of scammers to create a “full profile.” Such scenarios can lead to chain reactions of damage that could extend to credit scores.
Some security vulnerabilities in mobile operators allow attackers to intercept verification messages containing temporary card information. In particular, temporary cards are seen as one of the weak links in “SIM Swap” attacks.
The Misconception That Digital Cards Are “Temporary” and the Pitfalls of Permanence
It has been observed that temporary cards can remain active longer than expected in some cases. For example, at some US banks, even if a new physical card arrives, the temporary card will continue to be valid until the user manually cancels it. This can lead to double charges or forgotten subscriptions. Although some banks limit the validity period of temporary cards, automatically renewing transactions (such as Netflix or Amazon subscriptions) may continue to process through these cards. This is because payment systems do not carry a code that identifies the card as “temporary.”
Subscriptions defined via temporary cards are not automatically rejected when the card expires. This is because some payment infrastructures apply an acceptance logic based on “previous transaction history” rather than verifying the card's validity with the bank system.
Logistical Risks Arising During Card Delivery
Some banks do not track the process after issuing a temporary card and sending the new physical card by mail. According to a study conducted in Canada, 7% of cards sent by mail are delivered to the wrong person or lost. This creates a potential environment for fraud where the temporary card and physical card can be used simultaneously. In a case study conducted in the UK, the information on the temporary card was leaked before the physical card arrived, and the victimized user suffered losses from eight separate online transactions before the physical card arrived. This highlights the vulnerability of temporary cards to digital attacks.
In some cases of mail theft in the US, fraudsters target mailboxes by predicting when physical cards will arrive. In such cases, even if the temporary card information is not stolen, the physical card being obtained can trigger a chain of transactions.
How Are Temporary Cards Treated in Insurance and Refund Processes?
Some card insurance policies (e.g., travel insurance) classify transactions made with temporary cards as “excluded transactions.” This is because temporary cards appear as “short-term and unauthorized” in some systems. In chargeback (refund) requests, some banks may initially classify transactions made with temporary cards as “not worth investigating.” This slows down the process to the detriment of the user.
In the US in particular, when refunds or damages are requested for transactions made with temporary cards, some banks may avoid refund responsibility by claiming that the user “did not secure the card sufficiently.”
Temporary Cards as a Separate Category for Cybercriminals
It is known that cybercrime networks share information about temporary cards under separate headings. This is because, despite their short lifespan, these cards are considered more attractive as they can be used to initiate transactions before the bank's security systems are fully operational. Some fraud forums feature special “test product lists” for temporary cards. These lists anonymously share which temporary cards can be used with minimal scrutiny at specific stores.
Some hacker groups even write automated bots that target the first 10 minutes after a temporary card is created. These bots test the card's validity by making small transactions on pre-determined websites.
Moments When User Errors and System Vulnerabilities Converge
Most users do not fully configure security settings because they believe temporary cards are only “backups.” For example, many people skip setting a specific limit for these cards, even though the card limit can be manually set to as low as $1. Some users believe that spending history is not tracked while using a temporary card until the physical card arrives. However, most banks track these transactions as regular transactions, and in some cases, this can negatively impact user points.
Some banks display temporary cards in their mobile apps but do not provide details about the card's expiration date or transaction history. This lack of transparency prevents users from identifying harmful transactions in a timely manner.
How Effective Are AI and Automatic Security Systems for Temporary Cards?
Fraud prevention systems used by banks are typically trained based on physical card behavior. However, temporary cards have a “blank profile” in terms of behavioral data, making them harder for AI systems to analyze effectively. According to a study conducted in the US, some banks' AI-based fraud systems often flag the first three transactions made with a temporary card as “low risk.” This is because the algorithm acts without bias since there is no historical data, which opens a window of opportunity for malicious individuals.
Some fintech companies are developing additional layers that analyze customer behavior when temporary cards are used. However, these technologies are only active in some large banks. In small banks, temporary cards are generally only protected by basic verification systems.
Regulatory Gaps and Unregulated Areas
There are no clear definitions for temporary cards in international regulations. For example, although Visa and Mastercard systems technically define temporary cards as “active cards,” they do not guarantee user protection rights at the physical card level. The US CFPB (Consumer Financial Protection Bureau) has not defined a separate “protection class” for temporary cards. This creates a gray area between the user and the bank in cases of fraud—the bank may not accept liability.
In some European countries, transactions made with temporary cards have been classified as having an “uncertain status” under consumer rights. For example, in the UK, some court rulings have rejected user refunds on the grounds that transactions made with temporary cards do not constitute a “preliminary contract.” In Canada, there have been cases where products purchased with temporary cards were excluded from certain consumer guarantees (e.g., warranty period after chargeback). This situation arose because the card was not considered “fully valid.”
Fraud Schemes Related to Temporary Cards
Some fraudsters use temporary cards for transactions that do not appear to be stolen. For example, they can purchase small amounts of digital content with a temporary card, then return it and repeat the process with different card numbers to create a chain of fraud. Some fraudsters obtain the temporary card before the physical card is issued and use it to make “pre-order” transactions without the cardholder's knowledge. While these transactions appear normal in bank records, the victim suffers a loss before the physical card is ever received.
Temporary cards are sometimes targeted in phishing attacks. A message claiming to be from the bank is sent to the user with a link saying, “Your temporary card has been created, please verify.” Through this link, user information is collected and accounts are targeted even before the temporary card is activated.
Realistic Steps You Can Take for Personal Protection
After receiving a temporary card, users can manually limit the card's spending limit. However, 64% of users in the US are unaware of this feature. This simple precaution can eliminate a significant portion of the risk. Some banks do not enable an SMS alert system for temporary cards. Users must manually activate this feature. Therefore, it is critical to check the mobile notification system when the card is first issued.
Some apps for temporary cards offer single-use CVVs. However, this feature is not widespread and is unknown to most users. Yet these dynamic CVV systems can greatly increase security for online shopping.
E-commerce Platforms' Approach to Temporary Cards
Some e-commerce sites (especially those belonging to small businesses in the US) flag payments from temporary cards as “suspicious.” This is because these cards are frequently used in fraud schemes and have weak bank verification. Large e-commerce platforms (such as Amazon and Walmart) may request additional address verification for the first transaction made with a temporary card. This can lead to order delays or cancellations — often without the user even realizing the issue stems from the temporary card.
Some automatic payment systems (e.g., Uber, Spotify) do not reject temporary cards but flag them as “non-renewable sources.” This can result in the account being automatically closed when the subscription ends.