Check washing may sound like a niche issue, but it is actually one of the most widespread forms of check fraud impacting businesses nationwide. Criminals use powerful chemical or solvents to erase key details—such as the payee’s name and the check amount—turning legitimate checks into tools for theft. The rise in mail theft, especially from traditional blue postal boxes, has only increased the risk.
These schemes can cause significant financial losses, disrupt cash flow, drive up operational costs, and damage relationships with customers and vendors. Understanding how check washing happens and implementing safeguards can go a long way toward safeguarding your businesses’ finances and reputation.
How Check Washing Occurs
Check washing schemes often begin with stolen mail—long before a check ever reaches its intended recipient. Criminals frequently target mail in transit or focus on vulnerable collection points, such as outdoor residential mailboxes and blue USPS drop boxes. Once they obtain a check, they use chemical solvents to dissolve the original ink, typically removing the payee’s name and the check amount. These fields are then altered with fraudulent information, redirecting funds to accounts under the criminal’s control. The altered checks are often deposited quickly—sometimes within hours—before the issuing business or its bank detects any irregularities. In a short time, a legitimate check can be turned into a conduit for significant financial theft.
Why It’s Critical for Businesses to Remain Vigilant
The financial consequences of check washing can be severe—especially if the fraud is detected too late. Banks and other financial institutions may not fully reimburse losses if they determine that the business failed to take adequate preventative measures, leaving the burden squarely on the organization. Beyond the direct financial hit, there are often hidden costs: time and resources spent investigating the breach, coordinating with law enforcement, and resolving issues with affected customer accounts.
When altered or undelivered checks are intended for suppliers or other third parties, the damage can extend to your business relationships. Delays or payment discrepancies can erode trust, strain partnerships, and harm your organization’s reputation. Ultimately, proactive safeguards aren’t just about preventing financial loss—they’re essential to maintaining the confidence of your customers and business partners.
Practical Strategies for Protecting Your Business
Businesses do not need to be passive targets. There are several practical and easily implemented strategies that can significantly reduce your risk of falling victim to check washing schemes.
Start with something as simple as your choice of pen. Swap out traditional ballpoint pens for gel pens with water-based ink. Unlike oil-based ink, gel ink penetrates and bonds more deeply with paper fibers, making it far more resistant to chemical removal. This small change can go a surprisingly long way in protecting the integrity of your checks.
Next, reconsider how you mail checks. Dropping them into outdoor mailboxes—especially the familiar blue USPS drop boxes—has become increasingly unsafe. Whenever possible, take the extra step of handing over mail at a post office counter or using an indoor mail slot. Reducing the time checks sit unattended in the system makes them less vulnerable to interception.
Take advantage of bank security tools like Positive Pay. With this service, you provide your bank with a list of issued checks, including check numbers, dates, and amounts, and often payee names. When a check is presented for payment, the bank compares it to your list. If there’s a mismatch, the transaction is flagged for your approval. Because this process happens in real time, it offers a proactive line of defense rather than relying on detection after fraud has already occurred.
Ultimately, the most effective solution may be transitioning to electronic payments. Automated Clearing House (ACH) transactions are encrypted, faster, and far more secure than paper checks. They also come with enhanced tracking features, allowing you to confirm payment status and detect irregularities early.
What to Do If Check Washing Occurs
If you discover that one of your checks has been altered, time is of the essence. Start by contacting your bank immediately to report the fraude. They may be able to plce a hold on your account, flag or reverse unauthorized transactions, and initiate an internal investigation.
Next, gather all available documentation related to the incident. This may include a copy of the altered check, relevant bank statements, account activity logs, and any correspondence related to the transaction. This information will be essential in supporting your claim with both the bank and law enforcement.
File a police report to create an official record of the incident. Law enforcement agencies can use this information to identify patterns, connect related cases, and potentially track down the perpetrators. If you believe the check was stolen from the mail, also report it to the U.S. Postal Inspection Service—either online or through your local post office.
While the situation is being resolved, maintain open communication with any affected parties, such as vendors or customers. Transparency can help preserve trust and minimize disruption.
Finally, use the incident as a prompt to reassess your internal controls. Strengthening your check-handling procedures, securing your mail operations, and working closely with your financial institution to implement fraud-prevention tools can significantly reduce your risk of future incidents.
How CTBK Can Help
At CTBK, we understand the disruption and financial risk that check fraud can pose to your organization. Our experienced team of Certified Fraud Examiners and forensic accountants specializes in identifying, investigating, and preventing financial fraud—including check washing.
Through in-depth fraud risk assessments, we analyze your existing payment and control processes to pinpoint vulnerabilities and develop tailored strategies to strengthen your defenses. When concerns arise, our forensic accounting team conducts detailed investigations to uncover patterns of fraud, trace unauthorized transactions, and quantify financial losses.
We also believe prevention is just as critical as detection. That’s why we offer targeted fraud awareness training to equip your employees with the knowledge and vigilance needed to recognize and respond to red flags. Our team can also help design or enhance internal controls and anti-fraud programs that align with your operational needs and compliance requirements.
Should legal proceedings become necessary, CTBK provides litigation support and expert witness testimony to ensure you’re backed by objective, data-driven analysis every step of the way.
Partnering with CTBK means gaining a comprehensive suite of services dedicated to protecting your organization’s integrity, assets, and reputation.
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Kaitlyn M. Pettit, CPA, CFE Kaitlyn Pettit is a Senior Manager in the Forensic Services practice and has experience providing Audit, Forensic Accounting and Fraud Investigation, and Litigation Support Services, on behalf of clients. |
