"Our website's a bit dated but it still does the job."
We hear this constantly. And it's almost never true. A website that looks outdated in 2025 isn't just aesthetically embarrassing — it's actively sending customers to your competitors. The question isn't whether it's costing you business. The question is how much.
Here's how to find out.
Start with Google Search Console
If you don't have Google Search Console set up, do it today. It's free and it's the most direct window into how Google sees your website.
Log in and look at these three things:
Performance report → Average position over time. Are your average rankings declining? A graph that's been drifting downward over six months tells you Google is finding your site less relevant. That's organic traffic leaving.
Core Web Vitals report. This is where outdated websites get exposed. Google measures three things: Largest Contentful Paint (LCP, essentially load speed), Interaction to Next Paint (INP, responsiveness), and Cumulative Layout Shift (CLS, visual stability as the page loads). If you're seeing red or amber on these — especially on mobile — Google is actively downgrading your rankings compared to faster competitors.
Coverage report. Are there errors? Pages Google can't index? An old site often has broken pages, incorrect redirects, or crawl issues that mean content you think is being found simply isn't.
If you haven't set up Search Console, go to search.google.com/search-console and add your property. Verification takes five minutes.
Then look at Google Analytics 4
This shows you what's happening after people arrive — or rather, why they're leaving.
Bounce rate and engagement rate trends. If engagement is declining (people arriving and immediately leaving), something's wrong. Either you're attracting the wrong traffic, or the site experience is so poor that people leave before engaging. For old sites, it's usually the latter.
Mobile vs desktop breakdown. Go to Reports → Demographics → Overview. Look at what proportion of your visitors are on mobile, then look at conversion rate by device. If mobile conversion rate is a fraction of desktop conversion rate, your mobile experience is broken. This is extremely common on sites built before 2018.
Conversion rate. What proportion of visitors are taking the action you want — filling in a contact form, buying something, calling you? Even a rough figure is valuable. If it's below 1% for a service business, something's wrong. Below 2% for ecommerce, something's wrong.
Traffic trends. Look at organic traffic specifically over 12–24 months. A declining trend in organic sessions means your SEO position is weakening. That's future revenue being eroded right now.
The conversion rate calculation — what 1% is worth
This is the bit people find most clarifying. Run this calculation for your own business.
Take your monthly organic visitors. Let's say 2,000. Take your current conversion rate — let's say 1.5% (so 30 enquiries or sales per month). Take your average customer value — let's say £800 for a service business.
Current monthly value: 30 × £800 = £24,000/month.
Now imagine a redesigned website improved your conversion rate by 1 percentage point — from 1.5% to 2.5%. That's 50 conversions per month instead of 30. An extra 20 × £800 = £16,000/month. £192,000/year.
Even a 0.5% improvement is £8,000/month. £96,000/year.
That's what a poor conversion rate costs you. Not an abstract "lost opportunity" — real revenue from visitors who arrived, looked, and left.
A proper website redesign typically costs £8,000–£25,000. Do the maths.
How page speed kills revenue
This isn't theoretical. The relationship between page speed and revenue is documented across enough studies now to be settled.
Milliseconds of load time delay directly affect bounce rate and conversion. A one-second delay in page load time reduces conversion rates by around 7%. That's meaningful at any scale.
But the load speed problem for old websites is compounding. Slow load time hits you three ways simultaneously:
Direct conversion loss. Visitors leave before the page loads. They never see your offer.
Google ranking impact. Core Web Vitals are a ranking factor. Slow pages rank below fast pages, all else being equal. So your organic traffic shrinks at the same time.
Mobile amplification. On a 4G connection in the UK, which is what most mobile users are on, the gap between a 2-second site and a 5-second site is the difference between engagement and abandonment. Mobile performance penalties for old sites are typically worse than desktop.
Test your site right now at pagespeed.web.dev. If LCP is above 2.5 seconds on mobile, you're losing traffic and rankings to competitors who've invested in site speed.
What your competitors are doing to your customers
Here's a thought worth sitting with. When someone Googles what you do and you appear in the results — so do your competitors. They click yours. They click theirs. They compare.
If your site takes five seconds to load and looks like 2015, and your competitor's site loads in two seconds and looks professional and modern — where do you think they go?
Buyers don't think "oh, the website's a bit old but the company's probably fine." They think "this doesn't look professional" and move on. That's not unfair. It's human. We all do it.
Look at your three main competitors right now. What do their websites look like compared to yours? If you're honest with yourself, you'll know whether you're losing this comparison.
Our post on 10 signs your website needs a redesign goes into more detail on the visual and functional signals to look for.
Google's mobile-first indexing — and why old sites are penalised
Google switched to mobile-first indexing in 2023, which means it predominantly uses the mobile version of your website for indexing and ranking.
If your mobile site is a poor experience — slow, hard to navigate, with text that requires zooming to read — Google sees a poor experience. That's what gets ranked.
Many sites built before 2019 were built desktop-first, with mobile bolted on as an afterthought. Responsive design was less mature. The mobile experience is often genuinely inferior, and Google knows it.
Check your Search Console Core Web Vitals by device. If your mobile scores are significantly worse than desktop, you're being ranked on your worst performance.
Free diagnostic steps you can take today
You don't need to spend anything to understand whether your website is costing you business. Do these now:
1. Run PageSpeed Insights on your homepage and your most important landing page. pagespeed.web.dev. Write down your mobile LCP score. Anything above 2.5 seconds is a problem.
2. Open your website on your actual phone — not a computer. Not Chrome's device emulator. Your real phone, on a normal mobile connection. Walk through the process a customer would walk through. Find your product or service. Find the contact page or purchase path. Is it fast? Is it easy? Are buttons big enough? Does anything overlap or look broken?
3. Check Search Console for Core Web Vitals issues. If you don't have it set up, this is your first diagnostic task. The data it contains is too valuable to ignore.
4. Do a competitive Google search. Search for what you do plus your location. Look at every site on page one. Be objective. Is yours competitive with the best of them in terms of speed, design, and clarity?
5. Check your contact form. Actually submit it. Does the confirmation work? How long does it take to get a reply? Broken forms and slow responses are invisible revenue leaks.
6. Pull your mobile bounce rate in GA4. Compare it to your desktop bounce rate. A significant gap (more than 20 percentage points) suggests your mobile experience is substantially worse.
7. Look at organic traffic trend over 24 months. Declining? By how much? That's the magnitude of your SEO problem.
Patch or rebuild?
This is the honest question once you've diagnosed the scale of the problem.
Patching — adding a caching plugin, compressing images, fixing a few speed issues — makes sense when the underlying site architecture is sound, the design is competitive, and the problems are technical rather than fundamental.
Rebuilding makes sense when: the site is more than 4–5 years old and was never properly built, the mobile experience is poor throughout, the design is no longer competitive, the platform is outdated (old Joomla, Drupal 7, unmaintained custom PHP), or the technical debt is so significant that every fix creates two new problems.
Most businesses delay the rebuild too long. They patch, and patch, and patch. Each patch costs money and buys less time than the last. Meanwhile, the competitive gap widens and the revenue cost accumulates.
We've seen businesses spend £3,000 patching a site over two years, then spend £15,000 rebuilding it, when a £12,000 rebuild two years earlier would have generated an additional £60,000 in revenue over that period.
Get a proper SEO audit done alongside any rebuild conversation. Understanding the technical SEO state of your current site helps you make the right decision — and ensures the rebuild doesn't inadvertently destroy rankings you've built up.
What good looks like
An old website that's costing you business is being replaced by competitors' websites every day. That's not dramatic — it's just what happens when buyers have options.
The businesses that invest in proper websites treat them as revenue infrastructure, not as a sunk cost to be maintained indefinitely. They review performance quarterly. They know their conversion rate. They know their organic traffic trend. And when the numbers suggest a rebuild will pay for itself, they do it.
If you want someone to look at your current site honestly and tell you what it's costing you — and what a rebuild would realistically return — talk to us. No obligation, no pitch. Just an honest look at the numbers.
Also worth reading: why your website isn't generating leads. The overlap between outdated sites and lead generation problems is almost total.