What Is Strong Customer Authentication (SCA)?
Strong Customer Authentication (SCA) is a security process used to verify that a payment is being made by the genuine cardholder.
It requires customers to confirm their identity using at least two forms of authentication, helping reduce fraud and protect both businesses and consumers.
Why SCA Exists
As online and remote payments increased, fraud became harder to control using traditional checks alone.
SCA was introduced to:
- reduce fraudulent transactions
- protect cardholder data
- improve trust in digital payments
It is now a standard part of modern payment processing across the UK and Europe.
How SCA Works
SCA requires at least two of the following:
- Something the customer knows (e.g. password or PIN)
- Something they have (e.g. phone or banking app)
- Something they are (e.g. fingerprint or facial recognition)
This is often referred to as two-factor authentication (2FA).
What Is 3D Secure?
3D Secure is the most common way SCA is applied to card payments.
During checkout, the customer may be asked to:
- enter a one-time code
- approve the payment in their banking app
- use biometric verification
This confirms the transaction is genuine before it is authorised.
Why SCA Matters for Businesses
SCA directly impacts:
Fraud Prevention
Authentication reduces the likelihood of unauthorised transactions.
Chargeback Protection
When a payment is authenticated, liability for fraud can shift away from the business.
Payment Approval Rates
Modern authentication methods allow risk-based decisions, meaning legitimate transactions can still be processed smoothly.
Customer Trust
Visible security steps reassure customers that their payment is protected.
Common Challenges with SCA
If implemented poorly, SCA can:
- increase friction at checkout
- lead to abandoned transactions
- cause unnecessary declines
The key is balancing:
- security
- user experience
Where SCA Applies
SCA is typically used in:
- ecommerce transactions
- payment links
- remote payments (email, SMS, chat)
It is less commonly applied in:
- traditional MOTO (phone-only payments)
- certain recurring or merchant-initiated transactions
Why SCA Alone Isn’t Enough
SCA reduces fraud risk, but it does not eliminate it completely.
Businesses still need to:
- reduce exposure to card data
- secure all payment channels
- maintain consistent processes
The strongest approach combines authentication with secure payment handling.
Secure Payments Without Compromise
Strong Customer Authentication is a key part of modern payment security. When applied correctly, it protects your business from fraud while maintaining a smooth experience for your customers.
Request a demonstration from the SOTpay team of payment experts to understand how we can help you protect your business from payment fraud.
