Accessibility at Speed: How Vertical Helped Mastercard Open Banking Europe Meet WCAG in Under 5 Weeks. With the EU Web Accessibility Directive in full effect and the European Accessibility Act 2025 on the horizon, Mastercard’s Open Banking Europe site needed to prove WCAG compliance. Fast.
Engagement name: Open Banking Website Accessibility Optimization (WCAG)
Timeline: Kick off 28 May 2025 Validation 25 Jun 2025 Go live 5 Jul 2025
Client chain: Mastercard / Open Banking Europe – Armstrong – Vertical
Drivers: EU Web Accessibility Directive, European Accessibility Act 2025, RFP prerequisite
Target standard: WCAG 2.1 A AAA (highest feasible)
The problem? The site had already launched, and an external audit flagged over 200 accessibility issues across navigation, contrast, screen reader flows, and mobile rendering.
Mastercard had the audit. Armstrong had the brand and timelines. Vertical owned the remediation: HTML, CSS, JavaScript, WordPress PHP templates, across all components of the site.
We worked agile-style with Armstrong’s PMs and designers, cross-checking components daily. Nothing shipped until it passed both scans and screen reader flow checks.
Contrast Compliance:
Auto-adjusted dynamic theming for text to meet 3:1 (large) and 4.5:1 (standard) contrast—without changing Mastercard’s brand colors.
Search Rebuild:
Added hidden labels, live result announcements, and semantic list roles. Works flawlessly in screen readers now.
Heading Order:
Enforced clean heading structure using custom linters during page builds. No more H1 → H4 jumps.
Mobile Screen Reader Fixes:
Repaired modal focus traps, restored background inert states, and tested rendering across iOS/Android devices.
Reusable Components:
We created accessible navigation and support-section patterns now used on other Mastercard pages.
It wasn’t just about accessibility—it was about making accessibility part of the brand, not a layer on top.
Our deep experience with WordPress and enterprise compliance allowed us to move fast, without breakage.
Automated compliance score: ~25 % to ~93 % (+ 68 pp)
Critical issues: 27 to 0 (100%)
Serious issues: 156 to 12 (92%)
Legal exposure: High to Low (90 %)
WCAG Conformance
Lighthouse Accessibility
Critical Issues
Vertical pulled off in weeks what normally takes months.
Open Banking Europe by Mastercard is a public-facing platform supporting regulatory alignment and digital transformation in European financial services.
Vertical is a Toronto-based WordPress agency specializing in accessibility-first digital experiences. From audits to enterprise-grade remediation, we help teams meet compliance without compromising design or delivery speed.
[email protected]
verticalhq.ca
