Attribution, cost and ROI
SEO vs PPC budget: how to split your marketing spend
Written by the Top SEO Experts Team
Reviewed by Akshay VRLast updated 18 min read
Quick answer
Split by stage, because a local service business with little organic visibility should put most of its budget into ads. Put a smaller share into SEO foundations, then shift toward SEO as measured organic leads grow. The deciding number is cost per won job against gross profit.
Example You have $7,000 a month to spend and three people giving you three different ratios. One says 70/30, another says go all in on SEO, a third says never stop ads. All three are guessing, because a ratio has no money attached to it.
Two things settle it:
- What a job earns you
- How many months of spend sit ahead of the first organic lead
The model below uses an HVAC company, and every input can be swapped for your own.
How should a local service business split its budget between SEO and ads?
Fill the lead gap with ads, fund SEO as an investment, and move money only when measured organic leads justify it. Our test is simple. The SEO share should rise only while monthly organic leads stay at or above your SEO spend divided by your ad cost per lead.
What is the break-even count?
That break-even count anchors everything below. Say SEO costs $2,800 a month and a paid lead costs $90.92. SEO matches ads on cost per lead at 30.8 organic leads a month (2,800 divided by 90.92).
Key takeaway Below that count you are still investing. Above it, SEO is the cheaper source.
Two things follow. A fixed split can’t work across trades with different job values. And any split needs a review date, because the right answer moves as rankings grow or slip.
How much should you spend on marketing in total?
Set the total first, then split it. Published guidance for small businesses is thin and mostly secondhand, so a percentage can only be a sanity check.
Which percentage figures exist?
One often-repeated figure says the U.S. Small Business Administration recommends 7 to 8 percent of gross revenue for marketing and advertising. We read it only on a Chron small business article (accessed 22 Oct 2026).
That article applies it to businesses with under $5 million in sales and a 10 to 12 percent net margin. It shows no date for the SBA claim, and we could not open the SBA source.
What does Gartner report?
Gartner’s 2026 CMO Spend Survey press release (11 May 2026, accessed 22 Oct 2026) puts marketing budgets at 7.8 percent of company revenue in 2026. That is up from 7.7 percent in 2025. It surveyed 401 marketing leaders in January to March 2026, most at companies with over $1 billion in revenue.
Watch out It’s a large-company number, nothing like a plumber’s. We cite it only because it lands near the same range.
What does that look like in dollars?
Example Take a hypothetical business with $1.2 million in annual revenue. At 7 percent the budget is $84,000 a year, or $7,000 a month (1,200,000 x 0.07 / 12).
At 8 percent it is $8,000. Our model below uses $7,000.
Which check matters more than the percentage?
Then run the check that matters more than the percentage. Say $7,000 buys 77 ad leads at $90.92.
If 30 percent become jobs at $900 gross profit, that is 23.1 jobs and about $20,800 in gross profit. That’s roughly three dollars of gross profit per dollar spent, before overhead.
Our view Our rule of thumb: if your own version of that number is under two, fix the funnel before you argue about the split.
What does a lead cost in ads, and what does one cost in SEO?
An ad lead costs what the auction charges. An SEO lead costs your monthly SEO spend divided by the organic leads it produces that month.
The first is easy to see. The second is a ratio that changes with time.
What do ads cost?
For ads, LocaliQ’s search advertising benchmarks page (last updated 1 June 2026, accessed 22 Oct 2026) lists “Home & Home Improvement” with three figures.
| Measure | Home & Home Improvement |
|---|---|
| Average cost per click | $8.33 |
| Cost per lead | $90.92 |
| Google Ads conversion rate | 8.05 percent |
Its all-industry average cost per lead is $66.69. The chart sets the two cost-per-lead figures side by side.
Watch out The page says its data comes from thousands of its customers’ campaigns on Google and Microsoft Ads. It does not say whether “average” means mean or median. It gives no sample size or date range, and it lists no plumbing, HVAC or roofing rows.
We use $90.92 as an anchor. Replace it.
What do we know about SEO timing?
For SEO we trust no published cost-per-lead benchmark, so we quote none. What we can source is timing. Google’s SEO starter guide (last updated 10 Dec 2025, accessed 22 Oct 2026) says “Some changes might take effect in a few hours, others could take several months.”
Ahrefs’ study of how long pages take to rank was published on 15 May 2025 (accessed 23 Oct 2026). In one sample of 1 million random URLs, 1.74 percent reached the top 10 within a year.
In a second sample of 2 million random English-language URLs created in October 2023, the figure was 6.11 percent. It sampled random pages, not local service businesses.
How do you compute your own cost per lead?
To compute your own organic cost per lead, count leads by source for 90 days, using call tracking and form fields. Divide the month’s SEO bill by that month’s organic leads. Our SEO cost per lead post walks through the Search Console and call data side.
What does a worked model look like for an HVAC company?
Pick one trade, one job value and one close rate, then change them one at a time. These inputs are hypothetical, chosen to show the arithmetic, and don’t describe any real company.
The inputs are in the table.
| Input (hypothetical) | Value |
|---|---|
| Gross profit per booked job | $900 |
| Close rate | 30 percent of leads |
| Lead goal | 100 leads a month by month 12 |
| Ad lead cost | $90.92, the LocaliQ anchor |
All ads costs $9,092 a month (100 x 90.92). That yields 30 jobs (100 x 0.30). Each job costs $303 in ad spend (9,092 / 30) and leaves about $597 of the $900 before other costs.
The mixed plan spends $2,500 a month on SEO and fills the remaining leads with ads. We assume organic leads rise in a straight line from zero in month 1 to a steady level in month 12. That ramp is an assumption, not a forecast.
| Steady organic leads a month | SEO cost per organic lead | Monthly change vs all ads, after month 12 | Year-one extra cost | Cumulative break-even |
|---|---|---|---|---|
| 20 | $125 | Costs $682 more | $19,090 | Not reached |
| 30 | $83 | Saves $228 | $13,634 | Not within 60 months |
| 40 | $63 | Saves $1,137 | $8,179 | Month 20 |
| 60 | $42 | Saves $2,955 | None (about $2,731 ahead after 12 months) | Month 12 |
Read each row as one question: if SEO reached this steady level, would it beat all ads, and when? The 20-lead row never does.
The 30-lead row saves money each month but does not pay back within 60 months. The 40-lead row pays back in month 20, and the 60-lead row in month 12.
How are the columns worked out?
SEO cost per organic lead is $2,500 divided by the steady level. Monthly change is the steady level times $90.92, minus $2,500. Year-one extra cost is the mixed plan’s first-12-month spend minus all ads.
What is the decision rule?
Read the table as a decision rule. At 20 leads a month, SEO never wins on cost per lead at this ad price. At 40 it takes until month 20, nearly a year and eight months, to net out.
Our payback period post shows how to rerun this with a different ramp.
To build it yourself, use one row per month with five columns:
- Organic leads
- Ad leads needed to reach the target
- Ad spend
- SEO spend
- Cumulative difference against all ads
The SEO ROI calculator does the same arithmetic if you would rather not.
Watch out Organic leads can keep arriving after you stop paying for a given month’s work, while ads stop the day the budget does. The table counts none of that, so it’s tough on SEO and kind to ads.
How does the split change by trade?
It changes because gross profit per job and close rate set how much a lead is worth. The most you can pay per lead and still break even is gross profit times close rate.
Here is the same $90.92 ad lead price applied to three hypothetical trades. Gross profit and close rates are illustrative, so replace them from your books.
| Trade (hypothetical) | Gross profit per job | Close rate | Ad cost per won job | Left per job | Max break-even cost per lead |
|---|---|---|---|---|---|
| Emergency plumbing | $350 | 40% | $227 | $123 | $140 |
| HVAC | $900 | 30% | $303 | $597 | $270 |
| Roofing | $3,500 | 20% | $455 | $3,045 | $700 |
Our rule of thumb compares your actual cost per lead with that ceiling. Plumbing sits at 65 percent of it (90.92 / 140), HVAC at 34 percent, roofing at 13 percent.
Our view Above about two thirds of the ceiling, a small rise in ad prices wipes out the margin. That two-thirds line is our view, not a benchmark.
So the plumber has the strongest reason to build cheap organic leads early. A roofer can let ads carry growth while SEO builds. The HVAC company sits in between, and its season should decide.
Our trade posts compare channels in more depth: HVAC leads vs SEO, plumbing leads vs SEO and roofing leads vs SEO. For seasonality, see seasonal HVAC SEO and storm season roofing SEO.
Want to apply this to your site?
Not sure where to start? Get a plan for your own business.
How does the split change by stage?
Stage matters because early SEO spend buys almost no leads. Base the split on the organic leads you can measure today, never on the ones you hope to have.
Here are three stages for the $7,000 HVAC budget, as our view. Unlike the 100-lead model above, this is a fixed-budget comparison, and the organic leads at each stage are assumed. The last column is the SEO break-even from the earlier rule.
| Stage | Trigger | Ads / SEO | SEO break-even leads |
|---|---|---|---|
| 1. Starting | Under 10 measured organic leads a month | $5,250 / $1,750 (75/25) | 19.2 |
| 2. Building | 10 to 30 organic leads, profile and service pages in place | $4,200 / $2,800 (60/40) | 30.8 |
| 3. Established | Organic leads above the break-even for your SEO spend | $3,150 / $3,850 (45/55) | 42.3 |
Now compare each stage with all ads at $7,000, which buys 77 leads and 23.1 jobs at $303 each. Assume 8, 25 and 50 organic leads for stages 1, 2 and 3, and the 30 percent close rate.
The results:
- Stage 1 gets 65.7 leads and 19.7 jobs, or $355 a job.
- Stage 2 gets 71.2 leads and 21.4 jobs, or $328 a job.
- Stage 3 gets 84.6 leads and 25.4 jobs, or $276 a job.
In this example the mixed plan costs more per job than all ads until organic leads pass the break-even, and only stage 3 beats ads.
The chart below shows the cost per job for each plan. The figures are hypothetical.
Key takeaway That’s the honest shape of SEO spending: you pay first and collect later. If your cash can’t carry stages 1 and 2, say so before you start.
To place yourself, count organic leads from your call and form logs for the last three months. Use the lowest month, not the best one. A single good month is how businesses talk themselves into stage 3.
When should you shift money from ads to SEO, or back?
Shift when measured numbers cross a line, and ignore how the quarter feels. These rules are our view, written so a bookkeeper could apply them.
- Raise SEO share when organic leads for three straight months exceed your SEO spend divided by your ad cost per lead.
- Hold SEO share when organic leads are rising but still under that line and your cash covers the gap.
- Cut ad spend only as fast as booked jobs hold. Drop 10 to 15 percent, wait a month, and check total jobs, not ad leads.
- Keep an ads floor for peak weeks and for services you do not rank for.
- Raise ads when crews have capacity and cost per won job is below gross profit per job.
- Review dates: ads monthly, SEO quarterly.
A worked case: the HVAC company hits 32 organic leads in each of three months against a break-even of 30.8. Rule one says raise SEO share. Rule three says trim ads by about $700, which is 10 percent of $7,000, then check total jobs after 30 days.
Watch out Do not count ad-driven branded searches as organic wins.
Our post on leads from Google Ads, not SEO covers how to separate them.
Where do Google’s pay-per-lead ads fit?
They belong with ads, because you pay for each lead. Google’s Local Services Ads help page (accessed 22 Oct 2026) says “With Local Services Ads, you pay for valid leads,” and that invalid or low quality leads are not charged or may be credited.
The page describes a weekly budget that sets a monthly cap. It gives no prices, and eligibility depends on category and market, so check Google’s current rules for your trade. Compare these leads on cost per won job like any other paid lead.
What mistakes distort the split?
These are common failure points from how the math works, not measured rates.
Watch out The most expensive one is judging channels on cost per lead while close rates differ by source. Suppose phone leads closed at twice the rate of ad form fills (a hypothetical). A report that ignores the gap would starve the better channel.
Close behind is using one gross profit figure for every job type, so a cheap drain call and a $12,000 install (also hypothetical) look alike. Then there’s cutting ads the same month SEO starts, and watching total jobs fall.
The quieter ones:
- Copying a flat 70/30 from a blog as a target
- Counting Business Profile calls without tracking where they came from
- Never setting a review date, so an old split runs for a year
If cash is the constraint, our post on SEO on a budget covers what to prioritize. The home services marketing budget post walks through the whole budget.
What does this mean for your budget?
Start with what a job earns you. Work out cost per won job for ads, and compare it with gross profit per job. If ads leave a healthy margin and crews have capacity, the split can lean on ads.
Next, find your stage from the lowest of the last three months of organic leads. Fund SEO as an investment, and raise its share only when measured organic leads pass your break-even count.
Last, set a review date. Review ads monthly and SEO quarterly, and change one lever at a time.
What does the data not show?
It doesn’t show your numbers. Every job value, close rate, ramp and organic lead level here is hypothetical, with the arithmetic shown so you can swap in yours. The sources have limits:
- The LocaliQ benchmark is an average of unknown type and does not break out trades.
- The SBA figure is secondhand and undated.
- The Gartner survey is mostly billion-dollar companies.
- The Ahrefs study covers random pages from any site.
We found no sourced benchmark for SEO cost per lead in local services, and we have no home-services client results to publish. Our linear ramp is a modeling convenience. Real rankings arrive in steps, and some months bring nothing.
If your data disagrees with the table, believe your data. For a quick check, see the home services lead value math post.
What should you do this month?
Pull 90 days of leads by source, with outcomes. Work out cost per won job for ads, then your organic cost per lead. Pick your stage, set a review date, and change one lever at a time.
Run your own scenario in the SEO ROI calculator or size the investment with the SEO cost calculator. Costs depend on scope, so see our pricing page for how we frame it.
Frequently asked questions
What percentage of my marketing budget should go to SEO?
No sourced percentage fits every business. We tie the share to stage. It is about a quarter for a business with no measured organic leads, rising past half once organic leads cover the SEO bill.
Those are starting points to test against your own cost per won job, not industry standards.
Is SEO cheaper than PPC?
Per lead, only after organic leads exceed your monthly SEO spend divided by your ad cost per lead. Before that point SEO costs more, because spend runs months ahead of results. After it, SEO can be cheaper, though rankings and competitors can move the numbers either way.
How much should a small local business spend on marketing in total?
One widely repeated figure attributes 7 to 8 percent of gross revenue to the U.S. Small Business Administration, for businesses under $5 million in sales. We saw it only in a secondary article, so test it against your own cost-per-job math instead of adopting it as a target.
How long before SEO pays back compared with ads?
Google says some changes show up in hours and others take several months. In our hypothetical HVAC model, SEO that reached 40 organic leads a month netted out against all-ads spend around month 20. Real payback depends on competition, content quality and your close rate.
Should I stop PPC when SEO starts working?
Not all at once. Lower ad spend only as far as your crews and cost per job allow. Keep a floor for peak weeks and for services you do not rank for.
Cut in steps of 10 to 15 percent and watch total booked jobs, not only ad leads.
Do Google’s pay-per-lead ads count as SEO or PPC?
They are paid advertising. Google’s Local Services Ads help page says advertisers pay for valid leads.
Budget them with ads and compare them on cost per won job. Report them apart from organic so neither channel takes credit for the other’s work.
Which number should I check before changing my split?
Check cost per won job against gross profit per job, by lead source. If ads leave a healthy margin per job and crews have capacity, the split can lean on ads. If the margin is thin, or SEO leads are already above your break-even count, shift toward SEO.
Sources
- Chron Small Business, “What Percentage of Gross Revenue Should Be Used for Marketing & Advertising?”, accessed 22 Oct 2026
- Gartner, 2026 CMO Spend Survey press release, 11 May 2026, accessed 22 Oct 2026
- LocaliQ, “Search advertising benchmarks”, accessed 22 Oct 2026
- Google Search Central, “SEO starter guide”, accessed 22 Oct 2026
- Ahrefs, “How long does it take to rank”, 15 May 2025, accessed 23 Oct 2026
- Google Local Services Ads Help, accessed 22 Oct 2026
Want to apply this to your site?
Not sure where to start? Get a plan for your own business.
