What Is ROAS and Why Service Businesses Calculate It Wrong
ROAS stands for Return on Ad Spend. The formula is simple: revenue generated divided by dollars spent on ads. If you spent $1,000 on Google Ads and booked $5,000 in jobs, your ROAS is 5x — or 500%.
Simple formula. Widely misunderstood by service business owners — and by most agencies managing their accounts.
The problem isn’t the math. It’s what gets plugged into it. Most local service businesses are either tracking the wrong thing (leads instead of revenue) or not tracking conversions at all. Both scenarios make your ROAS number meaningless — and make it impossible to know if your ads are actually working.
This post is a straight-line walkthrough of what ROAS means for a service business, how to calculate it correctly, what good looks like in your vertical, and what to do if your number is off.
The ROAS Formula — And the Revenue Math Behind It
Here’s the baseline formula every owner needs to have memorized:
ROAS = Revenue from Ads ÷ Ad Spend
So if you’re an HVAC company running $3,000/month in Google Ads and those ads generate $15,000 in booked revenue, your ROAS is 5x. That’s a return of $5 for every $1 spent.
Search Engine Journal pegs the commonly cited minimum target ROAS at 4:1 — $4 back for every $1 in ad spend. That’s the floor. Businesses with high customer lifetime value, like HVAC or dental, can profitably operate below that threshold because the backend revenue extends well past the first job or visit.
The formula gets more useful when you break it into components. For a service business, the math looks like this:
- Ad Spend: What you paid Google this month
- Leads Generated: Calls + form fills attributed to those ads
- Close Rate: What percentage of leads become paying customers
- Average Job Value: Average revenue per booked customer
- Revenue from Ads: Leads × Close Rate × Average Job Value
Example: 40 leads × 40% close rate × $400 average job = $6,400 in revenue. Divide that by $2,000 in ad spend and you’re at 3.2x ROAS. That’s the number you bring to every agency conversation — not impressions, not clicks, not CTR.
For a deeper walkthrough on applying this to real campaign decisions, see our Owner Math — The Revenue Decision Framework.
ROAS Benchmarks by Vertical — What Good Actually Looks Like
Industry benchmarks matter here because “good ROAS” is not a universal number. A gym with $30/month memberships needs a very different threshold than a plumber with a $600 average ticket.
WordStream’s Google Ads industry benchmarks confirm this — home services businesses see fundamentally different conversion economics than e-commerce, which is why using a generic 4x benchmark to evaluate your HVAC or chiro campaigns leads to bad decisions in both directions.
Here are realistic ROAS targets by vertical, grounded in what we see running campaigns for local service businesses:
| Vertical | Avg. Job / Transaction Value | Target ROAS (First Job) | Lifetime Value Multiplier | Notes |
|---|---|---|---|---|
| HVAC | $350–$800 | 4x–7x | High (maintenance plans) | We’re running clients at $47 CPL |
| Plumbing | $250–$600 | 4x–6x | Moderate | Emergency demand drives higher close rates |
| Chiropractic | $150–$300/visit | 3x–5x (first visit) | Very High (recurring) | $38/patient acquisition cost on our campaigns |
| Dental | $200–$1,500+ | 3x–6x | Very High | LTV often exceeds $5k per patient |
| Gyms / Fitness | $40–$150/month | 4x+ (LTV basis) | High (retention dependent) | We’ve run gym campaigns at 4.2x ROAS |
| Realtors | $5k–$20k+ commission | 2x–4x acceptable | Moderate (referrals) | Long sales cycle; LTV matters more than first deal |
The takeaway: if you’re in a high-LTV vertical and your agency is optimizing for first-transaction ROAS alone, they’re leaving money — and decisions — on the table. See our Google Ads benchmarks by vertical for a deeper breakdown of what these numbers look like in real campaigns.
Why Most Service Businesses Can’t Calculate Their Own ROAS
The missing piece is almost always conversion tracking. You can’t calculate ROAS on revenue you can’t attribute. And most Google Ads accounts for service businesses are tracking either nothing or the wrong things.
Google Ads conversion tracking lets you assign dollar values to specific actions — phone calls, form fills, booking confirmations — so your campaign data reflects actual revenue signals, not just activity. When it’s set up correctly, you can see exactly which keywords, ads, and campaigns are generating bookings — and which ones are burning your budget on unqualified traffic.
When it’s not set up — which describes the majority of local service business accounts we audit — your ROAS is a guess. And you’re making $2,000–$13,000/month decisions on a guess.
The fix is straightforward: assign conversion values to every tracked action. Use your actual average job value. If your average HVAC service call is $450, set that as the conversion value for a booked call. Now your dashboard shows revenue math, not lead counts.
Once tracking is solid, Google’s Target ROAS Smart Bidding becomes a real tool — not just a checkbox. The algorithm uses your historical conversion value data to optimize bids in real time toward your target return. Without clean data feeding it, the machine is flying blind.
How to Use ROAS to Evaluate Your Current Agency (Or Your Own Campaigns)
Here’s the practical version. Pull your last 90 days of ad data and answer these four questions:
- What did I spend? Total Google Ads cost over 90 days.
- How many leads came from ads? Calls and forms attributed to paid search — not organic, not referrals.
- What did I close, and at what value? Apply your real close rate and average job value.
- What’s my ROAS? Divide the revenue number by the spend number.
If you can’t answer questions two or three with confidence, your tracking is broken and your ROAS is unknown. That’s not a minor issue — that’s a fundamental problem with how your account is being run.
If your ROAS is below 3x and you’re in a high-ticket vertical like HVAC, dental, or plumbing, your campaigns are likely underperforming. The causes are usually one of three things: wrong keywords targeting low-intent traffic, no negative keyword list, or landing pages that don’t convert. All fixable — but not if your agency is reporting impressions and CTR as wins.
LocaliQ’s home services benchmark data puts the average home services CPC at $6.55. At that cost-per-click, a $3,000 monthly budget gets you roughly 458 clicks. If your landing page converts at 5% (industry baseline), that’s 23 leads. Apply a 40% close rate and a $500 average job — you’re looking at $4,600 in revenue on $3,000 spent. That’s a 1.5x ROAS. Barely breakeven.
Now push close rate to 50%, improve landing page conversion to 8%, and tighten keyword targeting to high-intent searches: same budget delivers 36 leads, 18 booked jobs, $9,000 in revenue — a 3x ROAS. That’s the difference between a campaign that drains you and one that grows you. It’s not magic — it’s math and structure.
For a full breakdown of how to structure campaigns that produce these results, read our guide to Google Ads for local service businesses.
What to Do If Your ROAS Number Doesn’t Add Up
If you’ve run the numbers and something feels off — or your agency can’t show you a clear ROAS figure — you have one of three problems: bad tracking, bad campaign structure, or bad spend allocation. None of these fix themselves.
Start with tracking. Audit every conversion action in your Google Ads account. Is a phone call being counted as a conversion? Is a conversion value assigned? Is the call length threshold set to something meaningful — like 60 seconds minimum — so you’re not counting hang-ups as leads? Fix the tracking before touching anything else.
Next, look at where your budget is going. In most underperforming accounts, 20–30% of spend is going to broad-match keywords pulling in irrelevant searches. Pull your search terms report. If you’re an HVAC company seeing searches for “HVAC certification courses” or “DIY AC repair,” those clicks are costing you money and generating zero revenue.
Finally, evaluate your landing page. Sending paid traffic to a generic homepage is one of the most common — and most expensive — mistakes local service businesses make. Every campaign should go to a dedicated page that matches the search intent, shows social proof, and has one clear call to action: call or book.
Get those three things right and your ROAS will move. It always does.
If you want to know exactly where your current campaigns stand — and what your ROAS should look like given your vertical, budget, and market — book a Revenue Decision Review. It’s a free 30-minute session where we audit your current ad spend, run your actual owner math, and show you precisely what good looks like for your business. No pitch deck. Just numbers.