- A Bacs Service User Number (SUN)
- Access to a HSM (Hardware Security Module)
Automating payment processing helps finance teams reduce manual administration, improve payment security, and create more efficient payment workflows. Whether you’re looking for Bacs payment automation or automated Faster Payments, implementing the right infrastructure is essential to achieving straight-through processing (STP).
What is a Bacs Service User Number (SUN)?
A SUN (Service User Number), sometimes referred to as an Originator ID, is a unique six-digit identifier assigned to businesses that send or collect payments through Bacs and Faster Payments.
Every communication submitted through Bacs requires a SUN, creating an auditable record of each payment transaction. SUN information is maintained within Bacs systems and is used to identify the organisation behind each payment.
When payments appear on customer bank statements, the SUN enables banks to display the correct business name.
If a payment is disputed or a Direct Debit is charged back, the SUN is used to identify the organisation responsible for the transaction.
Without a SUN, businesses cannot fully implement Bacs payment automation or submit payment files directly into Bacs infrastructure.
What is a Smart Card?
A Smart Card is a security device used by businesses to validate and authenticate electronic payments and banking transactions.
Roughly the size of a credit card, it contains a secure memory chip that stores encryption keys and enables transaction authentication when connected to a Smart Card reader.
Smart Cards provide a secure approval process, but because they rely on manual authorisation, they can limit payment automation and make true straight-through processing difficult.
Pros of Smart Cards:
- Authorisation completed by an individual user
- Minimal hardware infrastructure required
- Lower initial setup costs
Cons of Smart Cards:
- Cards and security tokens can be misplaced
- Manual connection required for payment approval
- Increased risk of delays, human error, and password issues
For organisations looking to implement Bacs automation software, Smart Cards can become a bottleneck due to their dependency on human intervention.
What is a HSM?
A Hardware Security Module (HSM) is a secure hardware-based device used to generate, manage, and protect cryptographic keys.
HSM technology provides the foundation for secure authentication and encrypted payment file transmission. It is widely used across financial institutions, public sector organisations, education providers, and large corporates to support secure payment processing.
Compared with Smart Cards and other PKI authentication methods, HSM delivers greater resilience, stronger security, and enables full payment automation.
Most importantly, HSM supports unattended processing, allowing payment and collection files to be submitted automatically without manual approval.
Benefits of HSM for Bacs Payment Automation:
- Enables automated Bacs submissions and straight-through processing
- Supports remote access and secure connectivity
- Reduces manual administration and operational workload
- Enables completely automated payment and collection workflows
- Tamper-resistant hardware security
- Enterprise-grade encryption and authentication
- Considerations Before Implementing HSM
- Traditional onsite hardware can involve setup costs
- Administration is centrally managed
- Banks may require purchase of HSM certificates
- Internal hardware infrastructure may require ongoing maintenance
For organisations seeking scalable Bacs payment automation software, cloud-hosted HSM services provide the security benefits of HSM technology without the burden of maintaining physical infrastructure.
With AccessPay’s hosted HSM service, businesses can connect remotely and securely while only requiring the necessary bank-issued certificate.
Why Businesses Are Moving Towards Automated Faster Payments
While Bacs remains a popular choice for scheduled and high-volume transactions, many organisations are increasingly adopting automated Faster Payments to improve cash flow visibility and reduce payment delays.
Faster payments automation allows businesses to:
- Execute near real-time payment processing
- Improve supplier and payroll payment speed
- Reduce operational bottlenecks
- Minimise manual intervention
- Increase payment control and visibility
Combining Faster Payments with secure authentication infrastructure enables finance teams to modernise payment operations while maintaining compliance and security.
Choosing the Right Bacs Automation Software
| with AccessPay | without AccessPay | |
| Pricing Structure | Transparency: No price hikes or lock-in surprises, the price you see is what you pay. | Forced Migrations: Legacy providers often use new standards to force a 40–100% price hike. |
| Scalability | One Platform. Every Payment: As you grow, connect each new ERP or bank to a centralised payment hub for standardised control. | Disparate payment processes: Every new entity, bank, or payment type means another system to manage, more complexity and more room for error. |
| Automation | Bank & Payment Agnostic: Connect to over 16,000 banks and all leading ERPs to process payments without manual intervention. | Manual Intervention: Every payment file manually formatted, checked, and uploaded by hand. |
| Usage Costs | Annual Volume: No penalties for seasonal peaks or busy months. | Monthly Banding: You are charged overage fees if you spike in a single month. |
| Customer Care | Proactive: Rapid onboarding, regular check-ins and unrivalled support from our dedicated UK-based Customer Success team. | Reactive: Support shared across thousands of customers. No dedicated contact, and response times from hours to weeks. |
Ready to Automate Your Payments?
Automating Bacs payments and Faster Payments can help finance teams eliminate manual processes, improve efficiency, and strengthen payment security.
If you’re ready to modernise your payment operations, discover how AccessPay’s Bacs-approved payments and collections platform can support secure, automated payment processing and straight-through automation.
For more information about our BACS-approved, payments & collections software, register for a live demo.
