If you’ve ever launched a site, you probably know the frustration of watching it look flawless in Chrome and then fall apart in Safari or Edge. Every browser has its quirks, and skipping compatibility checks is a quick way to lose users. These days, making sure a site works everywhere isn’t optional – it’s part of the basics.
Across the UK, more and more teams are putting serious effort into solving this. Some companies go all in on testing, running endless setups until they catch every glitch. Others treat it as part of the bigger development picture, building it in from the start so nothing slips through the cracks later. Either way, the goal is simple: stop users from asking “why doesn’t this work here?” and give them the same smooth experience no matter what browser they use.
1. A-listware
At A-listware we take a broad view of software projects, working on design, engineering, testing, and support. We don’t treat cross-browser compatibility across the UK as a separate add-on but as something baked into every stage of the lifecycle. Our teams are spread across regions and cover both new builds and updates to existing systems, keeping security and clean code at the core.
When it comes to browser checks, we fold them into QA and development rather than leaving them to the end. That means writing standards-based frontends, testing across popular browsers and devices, and chasing down odd CSS or JavaScript issues when they appear. We also stick around after launch, making sure changes in browsers or libraries don’t quietly break things later.
Key Highlights:
- Development and QA combined into delivery
- Standards-first approach for predictable rendering
- Ongoing updates to handle browser and framework changes
- Secure coding practices with clear documentation
- Flexible models for long or short projects
Services:
- Web and mobile development
- Cross-browser and cross-device testing
- UI/UX design and reviews
- QA for both new and existing products
- Application support and help desk
- Cloud and infrastructure services
- Data and analytics
- Cybersecurity and compliance
Contact Information:
- Website: a-listware.com
- Phone: +1 (888) 337 93 73
- Email: info@a-listware.com
- Address: St. Leonards-On-Sea, TN37 7TA, UK
- LinkedIn: www.linkedin.com/company/a-listware
- Facebook: www.facebook.com/alistware
2. Talosmart
Talosmart works across several regions, including the UK, and covers a wide range of digital services. One of their main focuses is making sure sites don’t just look good on one browser but run smoothly everywhere. They treat compatibility as a foundation of development instead of leaving it as a quick test at the end.
Their process includes running sites through current and older browser versions, ironing out tricky CSS or JavaScript quirks, and keeping everything tied to industry standards. Beyond launch, they monitor browser updates and patch issues as they come up, which helps businesses avoid that sudden “this used to work yesterday” moment.
Key Highlights:
- Hands-on testing across multiple browsers and devices
- Fixes for CSS, JavaScript, and HTML inconsistencies
- Continuous checks and maintenance for stability
- Attention to user experience across platforms
Services:
- Cross-browser compatibility testing
- Web application development
- Frontend and backend builds
- Mobile app development
- UI/UX and graphics
- Game development
- Cloud and DevOps support
- Digital marketing
- Maintenance and support
Contact Information:
- Website: talosmart.com
- E-mail: info@talosmart.com
- Facebook: www.facebook.com/talosmart
- LinkedIn: www.linkedin.com/company/talosmart
- Instagram: www.instagram.com/talosmart
- Phone: +2348060494409
3. Web Alliance
Web Alliance is a UK-based company that builds tailored systems for businesses that need more than off-the-shelf tools. They develop CRM and ERP platforms, custom databases, and apps, and they also help modernise older systems so they keep up with current needs.
As part of their process, they test sites across a wide range of browsers to make sure users get the same experience regardless of where they land. Using tools like CloudTesting, they check compatibility on Chrome, Firefox, Safari, Opera, and even older Internet Explorer versions to catch problems before they cause issues.
Key Highlights:
- Custom CRM and ERP solutions
- Browser compatibility checks built into projects
- Updates for legacy systems alongside new builds
- Uses CloudTesting for wide coverage
- Long-term software support available
Services:
- CRM and ERP systems
- Browser compatibility testing
- Web and app development
- Legacy system revamps
- Databases and online portals
- Consultancy
- Ongoing maintenance
Contact Information:
- Website: www.web-alliance.co.uk
- E-mail: info@web-alliance.co.uk
- Facebook: www.facebook.com/pages/Web-Alliance-Limited/434950883246019
- LinkedIn: www.linkedin.com/company/web-alliance-limited
- Instagram: www.instagram.com/bespokecrm
- Address: 3 Duncan Close Moulton Park Industrial Estate Northampton, Northamptonshire NN3 6WL
- Phone: 01604 211 370
4. UK Site Design
UK Site Design builds custom websites with a big focus on responsive design and usability. They work with companies of different sizes and make sure that sites adapt smoothly not only to devices but also to different browsers.
They test their sites across major browsers and versions, making adjustments to avoid the common layout issues that can frustrate users. Their work leans heavily on established web standards, aiming for consistent performance and fewer surprises once a site goes live.
Key Highlights:
- Responsive and browser-aware design
- Checks across a variety of browsers and versions
- Strong emphasis on usability and performance
- Knowledge of both modern and older standards
Services:
- Cross-browser compatibility testing
- Responsive site design
- WordPress development
- Digital media and online marketing support
- Hosting
- Graphic design and UX
Contact Information:
- Website: uksitedesign.co.uk
- E-mail: studio@uksitedesign.co.uk
- Address: Pride Media Centre Unit T1 Shields Road Pelaw Gateshead. NE10 0HW
- Phone:01912837920
5. Pedalo
Pedalo is based in London and mainly works with WordPress and Drupal. They take on development, design, and long-term site support, often partnering with both businesses and non-profits. Their projects are usually ongoing, with steady improvements rather than just one-time builds.
They’re particularly careful with browser checks since every browser interprets code a little differently. To deal with this, they run sites through a range of browsers, including mobile and tablet versions, and use tools like BrowserStack to flag problems. Regular checks after updates keep things from breaking later on.
Key Highlights:
- London-based, focusing on WordPress and Drupal
- Development plus ongoing support and maintenance
- Regular testing across modern and older browsers
- Uses tools like BrowserStack and Browserling
- Consistency and usability are central
Services:
- Browser testing and monitoring
- WordPress development and audits
- Drupal development and upgrades
- Site performance optimisation
- Custom design and integrations
- Hosting and management
Contact Information:
- Website: www.pedalo.co.uk
- E-mail: info@pedalo.co.uk
- Twitter: x.com/pedalowebdesign
- LinkedIn: www.linkedin.com/company/pedalo-limited
- Address: 20-22 Wenlock Road, London N1 7GU
- Phone: 020 8747 3274
6. Saxon Websites
Saxon Websites, based in Coventry, works on WordPress and Magento sites along with databases, intranets, and ecommerce platforms. They keep projects small and hands-on, paying attention to both design and functionality.
They make cross-browser testing part of their routine for every new build. Sites get tested across multiple versions of Chrome, Firefox, Safari, Edge, Opera, and Internet Explorer. Clients often get screenshots as proof, showing exactly how the site looks before it goes live.
Key Highlights:
- Coventry-based, working with WordPress and Magento
- Builds websites, databases, and intranets
- Compatibility checks included by default
- Tests across multiple browser versions
- Provides screenshot evidence before release
Services:
- Web design and development
- Browser compatibility testing
- Ecommerce builds
- Databases and intranet systems
- Responsive design
- Maintenance and security
Contact Information:
- Website: saxonwebsites.co.uk
- Phone: 07597 278340
7. Blue Frontier
Blue Frontier is a full-service digital agency with offices in several UK cities. They cover design, development, marketing, and IT consultancy, working with clients in industries like healthcare, finance, and public services.
Part of their development process includes structured compatibility testing. They define which environments matter most, run tests across them, and fix issues before launch. The same approach can be used to review existing software, helping clients bring older systems up to modern standards.
Key Highlights:
- UK-based with offices in multiple cities
- Wide-ranging services under one roof
- Cross-browser and cross-platform checks
- ISO 9001 and ISO 13485 certified
- Experience across healthcare, finance, and public sectors
Services:
- Compatibility testing
- Web and app development
- Branding and design
- SEO and digital marketing
- IT consultancy and hosting
- MedTech software
- Legacy system reviews
Contact Information:
- Website: www.bluefrontier.co.uk
- E-mail: info@bluefrontier.co.uk
- Facebook: www.facebook.com/bluefrontiercouk
- LinkedIn: www.linkedin.com/company/bluefrontier
- Instagram: www.instagram.com/blue_frontier
- Address: Unit 1 Woodford Centre, Lysander Way, Salisbury, SP4 6BU
- Phone: +44 (0)1722 744 574
8. TestWorx
TestWorx, based in Reading, is focused on software testing rather than full development. They aim to make sure applications stay reliable and perform well under different conditions, offering both consulting and hands-on testing.
Their compatibility testing covers browsers, platforms, and devices, with checks across both desktop and mobile environments. By finding issues early, they help businesses avoid broken functionality or inconsistent designs when users switch from one setup to another.
Key Highlights:
- UK-based testing company
- Checks compatibility across browsers, platforms, and devices
- Provides both consulting and practical testing
- Scales services for different business sizes
Services:
- Browser and compatibility testing
- QA consulting
- Continuous testing support
- Functional testing
- Web and mobile app testing
Contact Information:
- Website: www.testworx.co.uk/index.html
- E-mail: info@testworx.co.uk
- LinkedIn: www.linkedin.com/company/testworx-ltd
- Address: TestWorx LTD Green Park, 200 Brook Dr, Reading RG2 6UB
- Phone: +44 1189496222
9. a1qa
a1qa is an independent software testing company with global reach. They work with startups, enterprises, and everything in between, testing everything from web and mobile apps to larger systems like ERP and cloud platforms.
For compatibility, they build a full matrix of environments – browsers, operating systems, devices, screen sizes, and more – and then test against it using both manual and automated tools. The result is a detailed report that shows where issues are and what to do about them before a product is released.
Key Highlights:
- Independent global testing provider
- Covers browsers, devices, and operating systems
- Manual and automated testing combined
- Builds tailored compatibility matrices
- Detailed reporting with recommendations
Services:
- Cross-browser testing
- Cross-platform checks
- Mobile compatibility
- Functional and performance testing
- Security and accessibility checks
- Regression and integration testing
- QA consulting
Contact Information:
- Website: www.a1qa.com
- Facebook: www.facebook.com/a1qa.software.testing
- Twitter: x.com/a1qa_testing
- LinkedIn: www.linkedin.com/company/a1qa
- Address: 3d Floor, 5-8 Dysart Street, Moorgate House, London, EC2A 2BX
- Phone: +44 204 525 7620
Conclusion
Cross-browser compatibility isn’t flashy, but it’s what keeps a site or app usable for everyone. The UK firms highlighted here approach it in different ways, whether through dedicated testing teams or by baking checks into the development process.
The key is making sure your project works consistently across browsers and devices, not just on the one you use every day. Ask how a company tests, what tools they rely on, and how they handle updates down the line. When compatibility is treated as part of the basics, users get a smooth experience without ever thinking twice about it.
