SEO vs. Google Ads: which traffic is actually cheaper?

The pitch for organic search is that it is free once it works, and the pitch for ads is that it works today. Both are true, which is why the argument never resolves in a meeting. What does resolve it is cost per lead — and there is published, independently collected data on that for both channels. Below is the comparison, including the two industries in the dataset where paid search actually comes out cheaper than organic.

Cost per lead: organic vs. paid, by industry

Figures are from First Page Sage's 2026 Cost Per Lead by Industry report, collected January 2022 – June 2025 across 30 industries and published in US dollars. The last two rows are included on purpose: in those markets, paid search produced leads more cheaply than organic. For scale on the paid side, WordStream's 2026 Google Ads benchmarks put the all-industry average at $5.42 per click and $66.69 per lead.

What the numbers say, and what they leave out

Across most of the dataset organic leads cost 13–47% less than paid ones, and the gap is widest in considered-purchase B2B categories where a single click can cost several euros. That is the honest headline. What the table cannot show is timing: the organic column describes a channel that was already working when it was measured. On day one it produces nothing, and the ramp to first meaningful traffic is typically three to six months.

Paid search has the opposite shape. It produces leads in the first week and keeps producing them at almost exactly the same unit cost in month one and month thirty. Nothing compounds. The moment the budget stops, so does the traffic — which is why treating ads as a growth strategy rather than a tap is where most budgets quietly leak.

The awkward number nobody quotes

The same research group publishes customer acquisition cost by channel, and it is much less flattering to organic than the cost-per-lead table. For B2B, their three-year averages put paid search at roughly $802 per acquired customer against $1,786 for what they call basic SEO — commodity keyword-and-meta-tag work. Only well-targeted, genuinely useful content ("thought leadership SEO", around $647) beat paid search.

That is the real finding, and it is not "organic is cheaper". It is that good organic is much cheaper and bad organic is more expensive than ads. Cheap SEO that never reaches page one is the single most expensive line item in this comparison, because it has a cost and no output.

What each one costs to start with us

SEO Starter is €499 one-time — a technical audit plus on-page optimisation across up to 15 pages, sitemap, robots.txt and Search Console. Google Ads Setup is €399 one-time and gets an account, one Search campaign across three ad groups, keyword research and GA4 conversion tracking live in three business days. Ad spend is separate and goes to Google, not to us — budget roughly €500 a month to gather usable data, and closer to €1,500 in the expensive sectors in the table above.

If you want to see where you stand before spending anything, the SEO Audit is free and includes a keyword gap snapshot against two competitors you name. It is a ranked PDF you can act on yourself.

How we would actually split a budget

For a business that needs enquiries this quarter and also in two years: run ads for the bottom-of-funnel, high-intent keywords where a lead pays for itself immediately, and put organic effort into the questions your buyers ask before they are ready to buy. Ads buy time; organic buys the cost base. Running only one of them is a choice to be either expensive forever or invisible until Q4.

The exception is a site with broken technical fundamentals. Sending paid traffic to a slow or badly structured page burns budget at both ends — you pay per click and convert worse than the benchmark. Fix the destination before you buy visitors for it.

Where AI search changes this maths

Both columns are under pressure from the same direction: a growing share of searches now end in an AI-generated answer with no click at all, which thins the top of the organic funnel and raises competition for the paid slots that remain. That does not flip the comparison, but it does change what "ranking" is worth. We cover the budget implications separately in SEO or GEO.

Sources

All cost figures above come from these independently published reports, checked July 2026.

• First Page Sage — Average Cost Per Lead by Industry, 2026 ↗

  Organic vs. paid cost per lead across 30 industries; data collected January 2022 – June 2025.

• First Page Sage — CAC by Channel, 2026 benchmarks ↗

  Three-year average customer acquisition cost by channel across ~120 firms: B2B PPC/SEM $802, thought leadership SEO $647, basic SEO $1,786.

• WordStream — 2026 Google Ads Benchmarks ↗

  All-industry averages for search advertising: $5.42 cost per click, $66.69 cost per lead; per-industry CPC from $1.63 (arts) to $9.87 (legal).