Why Your Google Ads Quality Score Is Tanking (And How to Fix It)
What Quality Score Actually Is
Google rates every keyword in your account on a scale of 1 to 10. That number determines how much you pay per click and where your ad shows up. A keyword with a Quality Score of 10 can pay less than half of what a keyword scoring 3 pays for the same position.
It's not a vanity metric. It directly hits your wallet.
Google calculates it from three components:
- Expected click-through rate (CTR): How likely someone is to click your ad compared to other advertisers bidding on the same keyword.
- Ad relevance: How closely your ad copy matches what the person actually searched for.
- Landing page experience: Whether your landing page delivers what the ad promised, loads quickly, and works properly on mobile.
Each of these gets rated 'above average', 'average', or 'below average'. You can see the breakdown in the Google Ads interface by adding the columns under keyword diagnostics.
Why Most Accounts Score Badly
We've audited hundreds of Google Ads accounts at this point. The same problems come up over and over.
Stuffing too many keywords into one ad group
This is the big one. If you've got 30 keywords in a single ad group, your ads can't possibly be relevant to all of them. Someone searching 'emergency plumber London' and someone searching 'boiler installation quote' have completely different intent. They need different ads and different landing pages.
The fix is straightforward: tighter ad groups with fewer, closely related keywords. Some people call this single keyword ad groups (SKAGs), though you don't need to be that extreme. You just need each ad group to tell a coherent story — one intent, one set of ads, one landing page.
Generic ad copy
'We offer quality services at competitive prices.' Right. So does everyone else.
Your ad copy needs to match the keyword as closely as possible. If someone's searching for 'accountant for contractors', the headline should say something about accounting for contractors. Not 'professional accounting services'. Not 'trusted financial experts'. The actual thing they searched for.
Include the keyword or a close variant in your headline. Address the specific problem. Give them a reason to click yours instead of the other seven ads on the page.
Sending everyone to the homepage
Your homepage is designed to explain your entire business. That's the opposite of what a paid search landing page should do. Someone clicked an ad about a specific thing — they want information about that specific thing, not a tour of your company.
Build dedicated landing pages. They don't need to be fancy. They need to match the ad, load fast, have a clear call to action, and work on a phone. That's it.
How to Actually Improve Each Component
Raising your expected CTR
Google compares your historical CTR against other advertisers. You can't game this — you need people to genuinely click your ads more often.
Write better headlines. Test different angles. Use the keyword in headline one. Put a benefit or differentiator in headline two. Don't waste headline three on your brand name unless you're a household name.
Pin your best-performing headline to position one if you're using responsive search ads. Google's machine learning is decent at optimisation, but it sometimes rotates in weaker headlines at the wrong time.
Improving ad relevance
This is almost entirely about structure. Tight ad groups with closely related keywords mean your ads can speak directly to the search query.
If Google is flagging ad relevance as 'below average', check whether your ad group contains keywords with different intent. Split them out. Write ads that speak to each group individually.
Fixing landing page experience
Page speed matters more than most advertisers realise. Run your landing pages through Google PageSpeed Insights. If your mobile score is below 50, that's a problem. Compress images, defer unnecessary scripts, and lose the massive hero video that takes four seconds to load.
Beyond speed:
- The headline on the page should match the ad headline.
- The call to action should be visible without scrolling.
- The page should work properly on mobile — not just 'technically load', but actually be usable.
- Don't hide your content behind popups or interstitials.
The Maths Behind Why This Matters
Google Ads uses an auction system, but it's not a simple highest-bidder-wins situation. Your Ad Rank is calculated roughly as:
So if your Quality Score is 5 and you bid £2, your Ad Rank is 10. A competitor with a Quality Score of 10 only needs to bid £1 to beat you. They pay less and rank higher.
Over thousands of clicks, a Quality Score improvement from 5 to 8 can reduce your cost per click by 30-40%. On a £10,000 monthly spend, that's £3,000-4,000 back in your pocket. Or the same budget buying you significantly more traffic.
Quick Wins You Can Do Today
- Check your keyword diagnostics. Add the Quality Score columns and sort by 'below average' ratings. That's your hit list.
- Split your worst ad groups. Find the ad groups with mixed intent and break them apart.
- Rewrite ads for your lowest-scoring keywords. Match the headline to the search term.
- Run PageSpeed Insights on your landing pages. Fix anything scoring below 50 on mobile.
- Add negative keywords. Irrelevant clicks tank your CTR. Check your search terms report weekly and exclude the rubbish.
When to Stop Worrying About Quality Score
Quality Score is a diagnostic tool, not the goal. If your campaigns are profitable and your cost per acquisition is where it needs to be, a Quality Score of 6 on some keywords isn't a crisis.
Focus on the keywords with the highest spend and lowest scores first. That's where the money is. A keyword you spend £5 a month on with a Quality Score of 4 isn't worth losing sleep over.
The accounts that perform best aren't obsessing over a single metric. They've got tight structure, relevant ads, and landing pages that convert. Quality Score follows from doing those things well.