A few weeks ago I was on an audit call with a client's marketing team. I worked through their Google Ads account line by line, and when we got to the cost-per-conversion on their biggest campaign, the call went quiet until one word was uttered: "Insane."
They weren’t wrong. That campaign cost just over $9,400 over thirty days, but only three of the reported actions were genuine new-patient enquiries. The report also counted "get directions" clicks and a price-guide download.
That puts the cost per genuine enquiry at roughly $3,100.
This didn’t happen because of weak ad copy, a bad offer or just poor luck that month, it was because there were two campaigns from one account fighting over the same vocabulary, with nothing in place to tell them apart.
The Setup: Two Clinics, One Shared Vocabulary
This client is a dental group. Two sites with the same owner in the same city providing two genuinely different services.
The main clinic does general dentistry like check-ups, hygiene, fillings and crowns. A few suburbs away they have a separate specialist orthodontic clinic doing braces, clear aligners and complex bite work.
Different practitioners in different places, with different websites and separate books.
There were two ad campaigns between them: a larger general dentistry campaign running around $9,400 a month, and a smaller orthodontics campaign running closer to $1,200.
On paper that is a tidy structure. In action it was anything but.
The problem is that a prospective client doesn’t know or care about the org chart. General dentistry and orthodontic searches share some vocabulary, and the way these campaigns were set up allowed searches intended for one clinic to reach the other.
Problem One: Match Types Were Not a Service Boundary
This is where most people who are relatively new to Google Ads are often caught out.
Phrase match used to mean exactly what it said. If you bid on "teeth whitening" as a phrase, the search had to contain that phrase, but Google's keyword matching now works on meaning, so even an exact match brings in close variants that share intent rather than wording.
What I said on the audit call was: "Google doesn’t really understand the difference. It just thinks they’re all the same." More precisely, our campaign settings were not keeping these two services apart.
| What the searcher typed | Which campaign served it | Where they landed | What happened |
|---|---|---|---|
| "orthodontist near me" | General dentistry | General dental homepage | No orthodontic offering on the page. Bounce. |
| "clear aligners cost" | General dentistry | General dental homepage | No pricing, no aligners. Bounce. |
| "braces for adults" | General dentistry | General dental homepage | Bounce. |
| "invisible braces [suburb]" | General dentistry | General dental homepage | Bounce. |
The platform makes a judgement about what a searcher means. That makes the search terms report essential when two service lines share vocabulary, because the match type alone does not establish the boundary you want.
This means that the general dentistry campaign, which was bidding on broad practice terms, was picking up a long tail it never chose:
Around a third of that campaign’s spend was going to searches with clear orthodontic intent. Those paid clicks were landing on the general dental page, which did not answer the question the searcher had asked.
The click was never the waste. The mismatch was.
Problem Two: The Larger Campaign Was Picking Up the Wrong Searches
This is the part that most business owners find genuinely surprising.
When eligible keywords target the same domain, Google’s prioritisation rules consider identical matches and relevance before using Ad Rank to resolve equal priority. This account had separate clinic websites, so that same-domain rule alone does not explain every choice between the campaigns.
Ad Rank depends on the bid, ad and landing-page quality, the search context and other auction factors. Campaign budget is not listed as a direct ranking factor. Budget can affect delivery and bidding decisions, but a larger budget does not establish why a particular campaign served.
The general dentistry campaign had a budget around eight times higher than the orthodontics one, and it was picking up orthodontic searches. That was an account-level mismatch we could see in the reports; the budget difference alone did not prove the cause.
The orthodontic clinic’s core service was being advertised through a campaign and landing page built for its sister practice.
Problem Three: It Leaks Both Ways
This is the detail an audit will miss if it only looks into the campaign that is obviously bleeding.
When we ran the search terms report on the small orthodontics campaign, we expected it to be clean, but it wasn’t. Around a fifth of its already low budget was going to general dentistry queries, arriving as exact-match close variants on terms like "dentist" and "dental clinic."
The smaller campaign was also spending part of its limited budget on searches better suited to general dentistry. The problem was present on both sides of the account.
Neither campaign had a clear service boundary. The larger one made the mismatch more expensive.
That reframes the fix: this is not about restraining a greedy campaign, but the account having no boundary between two services at all.
Problem Four: Everyone Was Judging It on a Number That Was Wrong
This goes back to the reported conversion total.
It included "get directions" clicks. The client’s reaction when we found it was: "Why would that even be set up as a conversion action?"
My instinct was that directions clicks were teaching the bidding system to favour an action that did not establish a new-patient enquiry. But the conversion settings mattered more than my first reaction.
Under standard goals, primary conversion actions are used for bidding when their goal is selected for the campaign. Secondary actions normally appear in "All conversions" for observation; the exception is a custom goal, where included actions can be used for bidding regardless of that setting.
When we checked afterwards, directions were already set to secondary. That changed the diagnosis: the secondary setting alone did not support my initial claim that these clicks were driving the bidding.
I was wrong about the mechanism, but the reporting problem was still real. The combined action count had shaped how the agency and client judged the campaign, even though only three actions represented people asking to become patients.
A directions click can be useful for understanding visits, but it does not tell you whether someone is a new patient, an existing patient or another visitor. Keep that separate from the enquiries you are trying to generate.
The Real Blocker Was Not Technical
The initial account changes were straightforward. The harder part was agreeing which clinic should own each type of search and how that decision should be funded.
Both clinics had separate budgets and separate people accountable for them. The general dentistry budget holder didn’t want their money funding a page that also promoted orthodontics, while the orthodontic side did not want to carry general dental traffic.
This resulted in the account doing the one thing nobody had chosen: spending the larger budget on searches it could not serve, all because no one owned the decision to stop it.
To their credit, the client said it before we had to: "I don't know if there's an elegant solution to that." There isn’t. There’s only the decision about who owns the searches, and then funding that decision.
That is an organisational problem wearing a Google Ads costume. If you are running more than one service line under one roof, this is the version of the problem you are most likely to actually have.
What We Did, In Order
We deliberately sequenced so the cheap, reversible work happens before anything that needs a budget conversation.
| Order | Action | Why first |
|---|---|---|
| 1 | Cross-negative both campaigns | Exclude clearly orthodontic searches from general dentistry, and clearly general-dental searches from orthodontics. Check match types and useful mixed-intent queries before applying negatives. |
| 2 | Apply service-specific negative lists to the relevant campaigns | Apply an orthodontic shared negative list only to campaigns that should exclude those searches. Check synonyms and singular or plural forms; keep terms for services you sell out of account-wide exclusions. |
| 3 | Audit every conversion action | Confirm the campaign’s selected goals and any custom goals; separate enquiry actions from observational actions in bidding and reporting |
| 4 | Fix the sitelinks | Clinic-specific campaigns get clinic-specific sitelinks; not the blog, not a generic fees page, not whatever was there in 2023 |
| 5 | Rebalance budgets to real demand | Only after 1 to 4 are done, once you can finally see what each campaign does when it is only serving its own searches |
The order matters. Review the exclusions and conversion settings with the person responsible for the account before changing them, then monitor what each campaign attracts. That gives the budget discussion a more useful starting point than a combined conversion total.
Check This In Your Own Account
Narrow checks, specific to this problem. For a broader sweep, our service business Google Ads self-audit covers the general health of an account, and our dental practice lead generation guide goes deeper into this sector specifically.
| Check | Where to look | What should worry you |
|---|---|---|
| Cross-contamination | Each campaign: Insights and reports → Search terms, sorted by cost | Terms that clearly belong to a different service line appearing in your top 20 by spend |
| Landing page mismatch | Take your top 10 search terms by cost, and open the page each one lands on | The page does not mention the thing they searched for |
| Conversion honesty | Goals → Conversions → Summary | Low-value actions used for bidding, including secondary actions included in a custom goal |
| Reported vs real | Compare your conversion count to enquiries that reached your inbox or CRM last month | A gap you cannot explain in one sentence |
| Budget vs intent | Compare each campaign's monthly spend against the service it is meant to sell | One campaign holding most of the budget while serving searches for a different service |
Run every check. Search overlap, landing-page mismatch and conversion-reporting errors can occur independently, so a clean search terms report does not clear the rest of the account.
What We'd Do Differently
Two things.
We would have run the search terms report on the small campaign first, not the big one. The obvious problem was the campaign that was wasting money. The insight was in the one that wasn’t because it proved the leak ran both ways and that the account had no intent boundary whatsoever. We found the right answer, just later than we needed to.
We would have stopped trusting the conversion count earlier. Everyone in that room was experienced, the reported number still shaped how a five-figure monthly spend was judged for months, but nobody opened it up to see what was going on inside. A conversion count you haven’t personally taken apart is a rumour, not a metric.
The wider lesson has nothing to do with dentistry. If your business sells two services that share vocabulary within one ad account, check whether their search terms, landing pages and conversion goals match the work each campaign is meant to win.
The first step is a search terms report you can run immediately. Use it to identify the boundary problem before deciding which settings or budgets need to change.
This article is based on a real client audit. The industry, business details and figures have been changed to protect client confidentiality, but the pattern, diagnosis and fix are all exactly as they happened.
If you have more than one service line running through a single Google Ads account, and you have never checked whether they are competing, this is a worthwhile exercise.
We are happy to run the search terms report with you and tell you plainly whether there is a boundary problem or not, with no pitch or obligation attached if the account is clean.
Book a time here: https://www.leadtree.agency/product/book-call
