Stop Fraud Bots Cold: Pre-Checkout Blocking Strategies for Shopify Stores

Hey everyone! As someone who spends a lot of time digging into the Shopify community forums, I often come across discussions that really hit home for store owners. Recently, a thread by a merchant named lovelyworld caught my eye, highlighting a pervasive problem many of you are likely facing: relentless card-testing bots.

You know the drill. Waking up to a flurry of small, fraudulent orders – usually just a few dollars each. It's not just the individual loss; as lovelyworld eloquently put it, these bots actively help criminals validate stolen credit card numbers. Every successful $2 transaction confirms a card is live, paving the way for bigger fraudulent purchases elsewhere. It’s a frustrating cycle, where merchants inadvertently serve as a daily card-validation service for bad actors, absorbing unrecoverable fees.

The Challenge: Pre-Checkout Fraud & Native Shopify Limitations

lovelyworld was battling a sustained attack, logging over 225 fraudulent $2 orders in a single month, resulting in about $85 in pure losses from transaction and processing fees. The bots even used US billing addresses, making IP blocking ineffective. The clearest red flag? A distinct email pattern: firstname.lastname###@gmail.com (a common name followed by 2-3 digits before the @gmail.com).

The core issue? Existing native Shopify tools fall short here:

• Shopify Fraud Control: Only supports simple "contains" text matching for emails – no regex, no order value, no product-level conditions.
• Shopify Flow: Powerful for complex logic and regex, but it only triggers after an order is placed. By then, transaction fees are already incurred and unrecoverable.
• Third-party apps: Many also lack pre-checkout regex email matching.

So, how do you block these patterns before the order hits your system and those fees pile up?

Community-Driven Solutions: Stopping Fraud Before & After Authorization

The community stepped up with two fantastic suggestions to combat this specific type of fraud.

Solution 1: Proactive Pre-Checkout Blocking with BeSure Checkout Rules

A direct answer to lovelyworld's plea for pre-checkout regex came from Sam9516, who recommended the BeSure Checkout Rules app. This app allows you to create "Validation Rules" that block checkouts based on specific conditions, including email pattern matching. This is exactly what we need to catch those firstname.lastname###@gmail.com patterns!

How to Set Up BeSure Checkout Rules for Email Pattern Blocking:

Here’s how you can implement this:

1. Install the App: Get BeSure Checkout Rules from the Shopify App Store.
2. Create a Validation Rule: In the app, create a new Validation Rule.
3. Choose Your Condition: Select "Email address" as your condition.
4. Input the Pattern: For lovelyworld's example (firstname.lastname###@gmail.com), you'd input something like firstname.lastname???@gmail.com. The ? acts as a wildcard, matching any single character. This allows you to catch variations like "john.doe123@gmail.com" or "jane.smithXY@gmail.com" if the number of trailing characters matches your pattern.
5. Set the Action: Configure the rule to "block checkout" and display a clear error message, such as "Checkout not allowed, please contact support." This immediately stops the transaction before any fees are incurred.

Sam9516 even shared a screenshot of how this rule should look:

Solution 2: Mitigating Fees with "Authorize Only" Payments

While the BeSure app handles pre-checkout blocking, what if a bot slips through or fraud signals only appear post-authorization? tim_tairli's suggestion offers a critical safety net: changing your payment provider to "authorise only" instead of "immediate capture."

With "authorize only," funds are reserved but not captured. This lets you use Shopify Flow (which triggers post-order) to analyze for fraud. If detected, you can cancel the order without capturing funds, avoiding unrecoverable transaction fees. If legitimate, you manually or automatically capture the funds.

How to Set Up "Authorize Only" Payments:

1. Go to Payments Settings: In your Shopify admin, navigate to Settings > Payments.
2. Choose Your Provider: For your primary payment provider (e.g., Shopify Payments), click "Manage."
3. Change Payment Capture Method: Under "Payment capture preference," select "Manually capture payment for orders."

This setting, combined with Shopify Flow automation for canceling high-risk orders, creates a powerful post-authorization defense.

The Bigger Picture: Shopify's Role in Native Fraud Prevention

While these workarounds are invaluable, lovelyworld’s original post also clearly requested Shopify enhance its native tools. Imagine if Shopify Flow’s powerful logic could act as a pre-checkout blocking tool, or if Fraud Control natively supported order value conditions and regex/pattern matching for emails. These improvements would be game-changers, offering robust, built-in protection that doesn't always require third-party apps for core functionality.

For those looking to start their own online store or migrate to a platform that's constantly evolving, Shopify offers a robust ecosystem. Discussions like these highlight critical needs and push for better solutions for all merchants. Combating fraud is an ongoing battle, but by leveraging clever community solutions and advocating for native platform improvements, we can make our stores safer and our operations more profitable. Stay vigilant, explore the tools available, and keep those bots at bay!