Opening a bank account used to mean a spending an entire afternoon at the branch, presenting physical IDs and signing paperwork. Even when banking moved online, the process remained arduous: opening an account could last days or weeks, with documents lost in transit or applications abandoned halfway through. 

Today, customers expect opening a bank account to be fast and seamless. When the competition offers same-day account opening and your process requires three business days or more (plus a printer), you're not just losing efficiency — you're likely losing customers. 

Qualified Electronic Signatures (QES), enabled by the EU Digital Identity Wallet (EUDI Wallet), represent a fundamental transformation in how banks can prioritise digitisation while staying secure. By combining government-verified identity credentials with cryptographically secure signatures, QES reduces account opening from a days-long paper shuffle to a minutes-long digital interaction. 

Here, we’ll dig into why QES is the more efficient (and compliant) method for completing customer onboarding, and how to make the switch. 

The problem with traditional, paper-based onboarding 

In today’s increasingly digital world, paper-based onboarding creates friction at every stage — whether at a bank branch or online. Sitting down with a representative in a bank branch takes time and requires plenty of physical documents, including government-IDs, proof of address, and more. And even when applications start out online, customers often need to download and sign forms physically, then either upload them to a portal or send them via post. All this causes time and delays, which in turn increase the chances that customers will abandon the process entirely. 

Physical documents also pose a security risks. Papers can be lost, stolen, or tampered with before reaching the bank. Unlike digital processes with cryptographic signatures and tamper-detection, paper offers no reliable way to prove a document hasn't been altered after signing.  

And that’s not to mention the operational cost of paper-based onboarding. Banks spend significant resources on manual document review, chasing missing signatures, and physical storage. Customer service representatives are tasked with fielding calls from unsatisfied or confused customers throughout the onboarding process, rather than helping current users.  

Compliance teams face their own challenges, as paper-based processes create fragmented audit trails. When regulators ask for documentation during reviews, reconstructing the customer journey becomes a manual detective exercise.  

With all these time, security, and efficiency roadblocks, it’s no wonder that banks are favouring fast and secure methods like QES in their KYC verification processes.  

Learn more about QES and why it matters for banking here. 

How QES transforms the customer onboarding journey 

Applying for a bank account online used to take several steps and incur long wait times.  

Before QES: 

1. The customer applies online  

2. The bank sends the documents by mail or email (printing required) 

3. Customer prints, signs, scans, and uploads or mails the documents 

4. Bank manually reviews for errors and missing signatures 

5. If errors are found, the customer may need to repeat the entire process 

6. Account activation: Up to 5-10 days 

At each step, complications build. Customers need access to printers and scanners, and documents may get lost in emails, uploading platforms, or postal services. Should problems occur, customers may abandon the process and seek out another bank with a more streamlined process. 

With QES: 

1. Customer applies online 

2. Identity verification takes place via EUDI Wallet in seconds 

3. Document review takes place on the customer’s smartphone 

4. They sign with QES using Face ID or fingerprint 

5. Account activation: Generally on the same day or within hours 

   
   

With QES-powered onboarding, the entire account-opening process happens on the customer's smartphone. No printing, no scanning, no waiting for documents to arrive. Identity verification and signature happen in a single flow, with government-verified credentials and cryptographic security built in. Errors are caught in real-time before submission. The customer is done in minutes, and the bank can activate the account immediately. 

The technical architecture behind QES-powered digital onboarding 

QES-powered onboarding relies on three integrated technical steps that work together to verify the customer’s identity, create legally binding signatures, and maintain compliance. Here's a breakdown of each step and how they work. 

Identity verification  

The process begins with identity verification through the EUDI Wallet. When a customer initiates account opening, the bank's system sends an API request to the customer's government-issued digital wallet. The wallet contains credentials that were verified by the member state when the customer enrolled — typically using their national ID card, passport, or other government-issued identity documents. 

The customer authenticates using biometric methods built into their smartphone: Face ID, fingerprint recognition, or PIN. This confirms that the person using the wallet is its legitimate owner. The wallet then shares verified identity attributes with the bank, in seconds. 

Behind the scenes, automated fraud detection systems check for anomalies, including suspicious patterns, credential inconsistencies, or known fraud indicators. Because the identity credentials come directly from government sources rather than customer-uploaded documents, the verification carries government-level assurance. 

Signature creation  

Here’s where QES takes centre stage. Once the customer’s identity is verified, they review account agreements and contracts on their smartphone. When they’re ready to sign, they authenticate again using their preferred biometrics, triggering the QES creation process. 

The signature is generated using a private cryptographic key stored in the secure element on the customer’s smartphone (a tamper-resistant chip that protects sensitive data even if the device is compromised). This key is uniquely linked to the customer's qualified certificate, which was issued by a Qualified Trust Service Provider (QTSP) and confirms the signer's verified identity. 

The QES embeds a timestamp showing exactly when the signature was created, cryptographic seals that detect any document tampering after signing, and the qualified certificate linking the signature to the verified identity. What’s more, an audit trail is automatically generated, recording every step: when documents were presented, when the customer authenticated, when the signature was created, and what was signed. 

Integration architecture 

When the customer completes the QES process, the bank's system receives the signed documents along with the verified identity attributes and complete audit trail. This data flows into the account opening workflow, where automated validation confirms the signature is valid, the identity is government-verified, and all required documents are complete. 

For banks, enabling QES-powered onboarding requires connecting to EUDI Wallet services and QTSP infrastructure through standardised APIs. The bank's onboarding platform must integrate with EUDI Wallet APIs to request identity verification and trigger QES creation, and establish connections with QTSPs (either directly or through identity verification platform partners) to handle qualified certificate issuance. 

The real-world impact: What banks stand to achieve 

Banks implementing QES-powered onboarding stand to see measurable improvements across their businesses: 

• Speed. Account opening is reduced from days to minutes, eliminating document processing delays and enabling same-day account activation.  

• Cost reduction. Banks eliminate expenses, including for printing, scanning, and physical storage. They also reduce document rework from errors and lowering overall operational overhead.  

• Customer experience. QES creates a mobile-first, frictionless process, delivering the instant gratification customers expect.  

• Compliance. QES provides automatic eIDAS compliance — the emerging standard for digital identity across Europe — with government-verified credentials that reduce fraud risk and shift liability away from banks. Built-in audit trails support regulatory review, and cross-border recognition across all 30 EEA member states enables seamless European expansion. 

  
  

Implementing QES in five steps 

If you’re ready to kick off QES-powered onboarding, here’s a roadmap to get you started: 

Step 1: Audit your current onboarding process 

Start by mapping every touchpoint where documents are exchanged, from initial application to final contract signing. Identify friction points causing customer drop-off, which could be printing requirements, upload failures, or unclear instructions. Calculate the actual time and cost per onboarding, including manual review time, rework for errors, and customer support overhead, so you have a baseline to measure improvement against.  

Tip: With eIDAS 2.0 and AMLA’s regulatory technical standards, QES-based onboarding is becoming the gold standard for EU-wide compliance. Learn more about the regulatory updates in this article.  

Step 2: Choose your technology  

Select an identity verification platform that handles EUDI Wallet integration and can manage the technical complexity of API connections and credential validation. Establish a QTSP partnership for qualified certificates, or choose a platform vendor that has existing QTSP relationships built in. Determine whether you'll connect directly to your core banking systems or use middleware to bridge your onboarding platform with existing infrastructure. 

Step 3: Design the digital journey 

Design a mobile-first interface that guides customers through identity verification and contract signing in one continuous flow. Provide customers with clear instructions for EUDI Wallet authentication, including setup guidance for customers who don't yet have wallets installed. If you’re using video identification as a fallback, ensure this use is documented as temporary measures. 

Step 4: Integrate and test 

Complete API integration with EUDI Wallet services and develop QES workflows that embed signatures into account agreements, loan documents, and contracts. Conduct thorough security testing to ensure cryptographic keys are properly protected and documents can't be tampered with after signing. Run user acceptance testing with real customers to identify usability issues and optimise the experience before full launch. 

Step 5: Launch and monitor 

Train customer support teams to troubleshoot EUDI Wallet issues and guide customers through the onboarding flow. Prepare compliance teams on new audit processes, including how to track verification methods and generate justification documentation for supervisory reviews. Use a phased rollout approach, starting with a pilot group before expanding to all customers, and continuously monitor metrics like completion rates, time-to-activation, and verification method distribution to iterate and improve. 

The future of QES 

QES is transforming more than just customer onboarding. As EUDI Wallet adoption grows, banks are expanding QES throughout the customer lifecycle, from digital mortgage documents and investment agreements to multi-holder business accounts and contract updates. What used to require branch visits or mailed documents now can now happen in minutes via a smartphone. And with QES recognised across all 30 EEA member states, cross-border expansion is becoming more seamless than ever before. 

The benefits — account opening reduced from days to minutes, stronger legal protection than paper signatures, and government-verified identity combined with tamper-proof cryptographic signatures — are self-evident. Implementation requires technology partners for EUDI Wallet integration and QTSP connections, but banks see rapid ROI through cost savings and improved customer experience. 

And, with EUDI and QES becoming the main recommendation under AMLA's verification hierarchy for European banks by July 2027, banks that implement QES now can position themselves ahead of regulatory requirements — and customer expectations. Those who wait will be playing catch-up. 

Transform Your Customer Onboarding with Fourthline 

Fourthline's identity verification platform enables seamless QES and EUDI Wallet integration, helping banks meet regulatory requirements while dramatically improving customer experience. 

Learn more about Fourthline's QES solution →