If you’re running Google Ads and spending $1,000 or more a month, there’s a number Google assigns to your account that you’ve almost certainly never seen, and it’s quietly controlling a significant portion of your costs.
It’s called your Quality Score. And your website is one of the biggest things driving it.
What Is Quality Score?
Quality Score is Google’s 1-10 rating of how relevant and useful your ad, keywords, and landing page are to the person searching. Google calculates it for every keyword in your account.
It isn’t just a grade. It’s a direct multiplier on your cost per click.
At Quality Score 1, you pay up to 400% more per click than someone with a Quality Score 7, for exactly the same ad position. At Quality Score 10, you pay roughly half as much.
| Quality Score | CPC Effect | Typical CPC (Plumbing) | Note |
|---|---|---|---|
| 10 | -50% | ~$5.25 | Branded searches only* |
| 9 | -30% | ~$7.34 | Excellent (long-term) |
| 8 | -20% | ~$8.39 | Good: our target |
| 7 | Baseline | ~$10.49 | Fair price |
| 6 | +17% | ~$12.27 | Average |
| 5 | +50% | ~$15.74 | Below average |
| 4 | +100% | ~$20.98 | Below average |
| 3 | +200% | ~$31.47 | Poor |
| 2 | +300% | ~$41.96 | Very poor |
| 1 | +400% | ~$52.45 | Critical |
QS 10 on generic keywords like “plumber near me” is essentially unheard of. It appears almost exclusively on branded searches, when someone types your company name directly. QS 8 to 9 is the realistic ceiling for service keywords and is an excellent result.
Baseline CPC source: WordStream 2024 plumbing industry benchmarks. CPC effect figures align with Google’s Ad Rank formula using QS 7 as the market-rate baseline.
This isn’t theoretical. Every time your ad is shown, Google runs an auction behind the scenes. Your effective bid in that auction is your actual bid multiplied by your Quality Score. A competitor with a lower bid but a higher Quality Score can outrank you and pay less. This is called Ad Rank.
The Three Components of Quality Score
Google calculates Quality Score from three components, each rated as “Below Average,” “Average,” or “Above Average”:
1. Expected Click-Through Rate (CTR)
This is Google’s prediction of how often your ad will be clicked when shown for a particular keyword. It’s based on your historical performance compared to other advertisers using the same keyword.
A well-written ad headline that clearly addresses the searcher’s intent, like “Emergency Plumber Dallas: Available Now,” will have a higher expected CTR than a generic one. This component is mostly within your control through your ad copy.
2. Ad Relevance
This measures how closely your ad matches the intent behind the search query. If someone searches “blocked drain Sydney” and your ad talks about water heater installation, your ad relevance will be low.
For plumbers, this usually means having tightly themed ad groups where your keywords, headlines, and descriptions all point at the same specific service.
3. Landing Page Experience
This is the component that most plumbers overlook, and the one your website controls most directly.
Google evaluates your landing page on several factors:
- Page load speed: especially on mobile
- Mobile-friendliness: does it work on a phone?
- Content relevance: does the page actually address what the user searched for?
- Navigability: can the user find what they need easily?
- Transparency: is it clear what your business does and how to contact you?
A slow homepage that loads in 6 seconds on mobile, used as the landing page for every ad campaign, will receive a “Below Average” landing page experience rating. That single rating drags down your Quality Score across your entire account.
Why Most Plumbing Sites Score Poorly
In 2024, we tested the top 100 plumbing websites by Google Ads spend in the US. Fewer than 3% scored above 70 on Google’s PageSpeed test for mobile.
The average was in the 20 to 72 range.
This matters because Google uses your PageSpeed score as a direct input into the “landing page experience” component of Quality Score. A site scoring 25 on mobile is giving Google a clear signal: this page loads slowly, the mobile experience is poor, and users are likely to leave before they find what they need.
The result is a landing page experience rating of “Below Average,” and a Quality Score that sits in the 4 to 5 range for most keywords.
The Compound Effect
Here’s where the impact compounds. When your Quality Score is 4 to 5, typical for a slow plumbing site, you’re not just paying more per click. You’re also:
- Appearing lower in the search results (Ad Rank determines position)
- Spending your budget faster on fewer impressions
- Converting at a lower rate because the landing page that caused the poor QS is also failing visitors
A plumber spending $2,000 per month at an average QS of 5 is effectively wasting $667 of that budget on the slow site penalty. At QS 5, you pay 50% above the market rate, meaning one third of every dollar spent is the penalty. Fix the site, and that money goes straight back into clicks.
The Three Things That Actually Move Your Quality Score
1. Fix the landing page speed first. This is the highest-leverage change you can make. Moving from a 30 score site to a 95+ site can shift your landing page experience from “Below Average” to “Above Average” for your entire account. Everything else improves as a result.
2. Use dedicated landing pages per campaign. A page built specifically for “emergency plumber [city],” with that exact headline, a direct call to action, and no navigation distractions, signals strong content relevance and improves ad relevance simultaneously.
3. Tighten your ad groups. Single keyword ad groups (SKAGs) or tightly themed ad groups ensure your ads match your keywords closely. This improves the expected CTR component.
What Each Score Level Actually Means for Your Business
QS 7: the floor with a fast, well-built site. When your landing page experience is “Above Average” and your campaigns are reasonably structured, QS 7 is where you land. You’re paying the market rate, no penalty. For most plumbers upgrading from a slow site, this is already a significant improvement.
QS 8 to 9: what well managed campaigns unlock. Reaching 8 or 9 requires your Google Ads campaigns to be tightly structured alongside the fast website, with the right keywords in the right ad groups, ad copy that closely matches what people are searching for, and a landing page built specifically for each campaign. At QS 8 you’re paying 20% less per click than baseline. For a plumber spending $2,000 per month, that’s $400 back every month, or the same number of leads for significantly less spend.
QS 10: not a realistic target for service keywords. A score of 10 almost exclusively appears on branded searches, where someone types your company name directly into Google. On generic service keywords like “emergency plumber” or “plumber near me,” QS 10 is essentially unheard of. QS 8 to 9 is the realistic ceiling and is an excellent result.
The Bottom Line
Quality Score isn’t a mysterious Google algorithm you can’t control. The website handles the landing page experience component, which is the foundation everything else is built on. A fast, purpose-built landing page gives Google the signals it needs to reward you with a high score. Quality Score builds as your campaign runs and Google collects data - most plumbers see their score reach 7 or above within the first 3 months of advertising. Getting to 8 or 9 from there is a campaign management question, not a website question.
A slow, generic homepage used as the landing page for every ad is the single most common cause of poor Quality Score in trades businesses. The site is always the right place to start.
Source: Google Ads Help, “About Quality Score”: support.google.com/google-ads/answer/6167118. WordStream 2024 Plumbing Industry Benchmarks.