As digital payments continue to grow, so do the tactics used by bad actors to exploit them. One that has gained renewed attention across the payments industry is the BIN attack, with Inecto reporting that incidents have risen by 80% since 2020 (Kitos, 2025). While it may sound technical, BIN attacks create serious operational, financial, and compliance risks.
For many merchants, the first sign of trouble isn’t an alert; it’s a consequence. A frozen account. Unexpected chargebacks. A call they weren’t expecting. Understanding how BIN attacks work — and how you can prevent them — goes a long way towards protecting revenue, reputation, and customer trust
What Is a BIN Attack?
A BIN attack is a type of card-testing fraud that targets the Bank Identification Number (BIN). It’s the first 6–8 digits of a credit or debit card number that identify the issuing bank and card type. Fraudsters use automated scripts to generate thousands of possible card combinations and submit rapid, low-dollar authorization attempts to test which card numbers are valid. Once identified, they are often sold or used for larger fraudulent purchases elsewhere.
Even though transactions may be small at first, the downstream impact can be significant:
- Account disruptions or processor intervention
- Increased chargebacks and fraud monitoring costs
- Higher interchange and network scrutiny
- Potential card network fines
BIN attacks also degrade customer trust. Cardholders may associate the fraudulent activity with the merchant they see on their statement, even if that merchant was only unknowingly involved.
Pay Attention to Stay Ahead — Prevention is a Shared Responsibility
BIN attacks quietly erode customer trust. Cardholders often associate fraudulent activity with the merchant's name they recognize on their statement, even when that merchant was unknowingly involved. Once trust is lost, it’s difficult to recover, regardless of where the fault actually lies.
Preventing attacks relies on shared visibility and early awareness, as risk can extend beyond a single merchant account. Portfolios with multiple BIN attack victims can trigger scrutiny from sponsor banks and card networks, impacting entire programs, partnerships, and growth strategies. Partners and their merchants should stay alert to common warning signs, including:
- Sudden spikes in low-dollar authorization attempts
- Short bursts of high-volume declines across similar card ranges
- Transaction patterns that don’t align with normal customer behavior
- Unexpected inquiries or alerts from processors or risk teams
How Payarc Helps Prevent Attacks
According to Government Executive, early fraud prevention activities can cut fraud losses by an average of 40% when properly implemented across an organization’s systems and processes (Miller, 2018). Achieving that kind of impact requires continuous monitoring, intelligent signals, and the ability to act quickly. This layered approach is the foundation for how Payarc address fraud detection as a whole, and not just BIN attacks.
Key protective measures include:
- Real-time monitoring to detect abnormal transactions and rapid authorization attempts
- Rapid risk signals that flag suspicious card-testing behavior
- Account-level safeguards that allow quick responses when patterns emerge
- Dedicated risk and compliance teams actively monitor activity across the platform 24/7.
In an environment where fraud tactics evolve quickly and quietly, prevention is no longer about reacting after the fact. It’s about maintaining visibility, acting early, and partnering with a payments provider built to protect both growth and trust at scale.