"Combining SEO and SEA: how to make organic and paid traffic work together"

The question “SEO or SEA” comes up almost every day, from start-up online shops to established B2B companies. Usually, it’s the wrong question. Not because the budget is unlimited, but because the two channels solve different problems: one buys visibility, the other builds it up. If you manage them as part of a single strategy, they will feed into each other. Advertising data determines where you focus your content, and better pages drive down your cost per click.

Below, you can read what this difference means in practice, the four mechanisms through which the channels reinforce each other, what AI Overviews do with both of them, and when to choose which one for what purpose. This is followed by five steps to align them, an estimate of the combined cost, how the budget allocation shifts over the years, how to measure performance accurately, and which mistakes are quietly eating away at your budget.

What the difference between SEO and SEA means in practical terms

SEO (Search Engine Optimisation) helps you secure your place in the organic results through technical optimisation, content and authority. SEA (Search Engine Advertising) buys a position above or amongst those results, charged per click. Together, they form search engine marketing, or SEM. The full definition of SEA, including campaign types and bidding strategies, can be found in What is SEA?. This is about how that difference affects your planning and your wallet.

• Speed: a campaign can go live within hours, whereas SEO takes an average of three to six months to produce noticeable results and six to twelve months to achieve strong rankings for competitive keywords.
• Cost structure: with SEA, you pay per click; with SEO, you pay upfront for work that continues to deliver results afterwards. With SEO, the cost per visitor falls as your ranking improves; with SEA, it remains the same or increases.
• Longevity: if you pause the campaign, you’ll disappear from view that very afternoon. An organic ranking will remain for a while longer, even if you reduce your investment for a month.
• Flexibility: with SEA, you can test seasonal promotions, price changes and new markets in a matter of days. SEO, on the other hand, requires a consistent approach that you don’t change every quarter.
• Trust: many searchers perceive an organic result as more credible than an advert, particularly when making more complex purchases.
• Data: SEA provides usable conversion data within weeks, whilst SEO provides richer behavioural data, but much later.

Both channels carry a risk profile. SEO is vulnerable to algorithm updates that can affect a strong ranking within a week. SEA makes you dependent on your budget and on click prices, which rise every year in competitive markets. Neither is a safe haven, and that is precisely why diversifying across two channels has value in itself.

There’s one misconception that needs to be cleared up straight away: advertising does not improve your organic ranking. The ad auction and the organic algorithm are separate systems, no matter how much you spend. What SEA does, however, is provide data and build brand awareness, and in the long run this leads to more searches for your brand name. Indirectly, not because you’re paying Google.

Four ways in which the channels reinforce one another

Synergy does not lie in vague cross-fertilisation. There are four mechanisms that you can identify, measure and manage.

SEA data helps you refine your SEO

The biggest advantage of advertising is the speed at which you learn. Which search terms actually bring in customers, which message resonates, and which landing page converts? You’ll have the answers within weeks, whereas SEO takes months. Use them as a priority list for your content: that way, you won’t be writing articles based on search volume and assumptions, but on proven commercial demand.

For example, run adverts for a month using five keywords you want to rank for organically, see which ones deliver the best cost per lead, and put those at the top of your content plan. That way, you’ll know there’s a genuine intention to buy even before the first piece of content is written.

SEO work immediately reduces your advertising costs

Google assesses your adverts based on more than just your bid. The Quality Score, a rating on a scale of 1 to 10, helps determine your position and your cost per click, and is based on the expected click-through rate, the relevance of the advert and the landing page experience. This last component accounts for approximately 39 per cent of the score. This means that technical SEO and good page content are not simply an additional cost alongside your adverts, but a way to boost their effectiveness: a fast, mobile-friendly page that provides a precise answer to the search query will lower your CPC for exactly the same position.

The same principle applies on the advertising side. Google reports that advertisers who improve the quality of their responsive search adverts from ‘Poor’ to ‘Excellent’ achieve, on average, 15 per cent more clicks and conversions. The same ad copy, the same budgets – just better execution.

Duplicate listings on the results page

If you appear both organically and via an advert for the same keyword, you take up more space and push a competitor down the rankings. What’s more, this repetition helps with brand recognition: if people see you twice on the same page, they’re more likely to remember your name and will be more inclined to search for your brand directly in future. There is, however, a limit to this dual presence, and we’ll discuss this further later on in the section on mistakes.

Covering the funnel and bridging the gap between launches

Think in terms of the customer journey and the division of tasks will naturally fall into place. At the top of the funnel, where people are exploring and comparing options, informative SEO content does the job: explanations, comparisons and answers to follow-up questions. At the bottom of the funnel, for search queries with a clear intention to buy, SEA is effective because competition is fierce and speed is of the essence. Retargeting also reaches visitors who arrived organically but weren’t yet ready to convert.

The same principle applies when launching a new page or service. Building authority takes time, so let SEA bridge that gap: you’ll start attracting visitors and gathering data from day one, whilst your organic rankings grow in the background.

What AI Overviews can do with both channels

There are figures circulating about AI Overviews that seem almost to contradict one another. This is because they measure different things: one study looks at click-through behaviour, another at CTR loss for a single position, and a third at how often such a summary appears at all. When compared side by side, the picture looks like this.

Research into click behaviour shows that, for searches using AI Overview, users click through to a website in around 8 per cent of cases, compared with 15 per cent for searches without it. The analysis of the DDMA Regarding how new search features are changing the playing field, the organic position one sees a drop in CTR of between 34 and 64 per cent as soon as an AI Overview appears above it. This refers to clicks, not impressions.

How often this happens is a separate question. Research by Semrush and Ahrefs shows that AI Overviews appear in 8.7 per cent of commercial searches: precisely the type of search that generates your revenue has, so far, been the least affected. Informational searches are taking the brunt of the impact. Add to that the variation by country: in the Netherlands, an AI Overview appears in 14 to 15 per cent of desktop searches, whilst in Germany the figure is less than 1 per cent. These figures do not therefore contradict each other; they measure different scopes. The full impact analysis can be found in AI Overviews and Your SEO Strategy.

There is also a reverse trend: pages cited as sources in an AI Overview actually receive more clicks. Visibility in the AI response thus becomes a factor in its own right to focus on. You can read about how to build that visibility in generative engine optimisation. One thing you don’t need to do: create a separate llms.txt file. Google confirms in its own documentation on optimising for AI features that Search does not use that file and that a separate Markdown layer for AI is unnecessary.

The landscape is also shifting for SEA, though less dramatically. Adverts remain part of the standard auction and do not disappear behind the AI response, although the visible clickable area decreases as the summary takes up more of the screen. Since its roll-out in 2025, Google has been displaying adverts within AI Overviews and AI Mode in the United States. These placements are not yet available in the Netherlands; Google expects to roll them out more widely later in 2026. You do not need to set up a separate campaign type for this: the inventory is served from existing Search, Shopping and Performance Max campaigns and via AI Max for Search. Anyone working exclusively with manually configured, narrowly defined Search campaigns will therefore miss out on these placements once they go live here.

When do you choose what?

There is no single piece of advice that applies to every business, but the patterns are recognisable enough to serve as a starting point.

Start with SEA if your website is new and has hardly any authority yet, if you need to generate revenue or leads quickly for a launch or seasonal promotion, if you don’t yet know which message converts, or if you’re in a market where organic rankings take years to achieve. Prioritise SEO if you’re building for sustainable growth; if click prices in your sector are so high that advertising is consistently loss-making; if you’re serving a niche with limited organic competition; or if your domain already has authority that you want to build on further.

Imagine you run a garden centre. In that case, your traffic comes in two waves at the same time: all year round, people search for plants, maintenance tips and gardening advice, and a few times a year you experience a peak around seasonal promotions. You capture the steady flow with SEO, by optimising the site both technically and in terms of content so that organic traffic grows steadily. You capitalise on the peak with SEA, specifically during the weeks the promotion is running. This is a scenario, not a measured client result, but it does illustrate the logic: SEO covers the baseline traffic, whilst SEA covers the spikes.

One fair point to make. On a small budget, you can’t do everything at once. SEA requires sufficient volume to learn from it; if your figures are too low, you’ll mainly be paying for the learning curve without gaining any insight. In that case, it’s wiser to lay the organic foundations first and add adverts once you’ve got something in place. Conversely, in an extremely competitive market where organic growth takes years, you should actually start with advertising to attract converting visitors straight away.

In most cases, we recommend starting both at the same time: running SEA to drive traffic and achieve initial visibility, whilst laying the foundations for SEO. After three to six months, you’ll know which organic rankings are achievable and which keywords will continue to require an advertising budget. That’s the time to rebalance your strategy.

Five steps to aligning SEO and SEA

1. Link Search Console to Google Ads and view the report on paid and organic traffic. In that report on paid and organic traffic For each search query, you can see how you’re performing across both channels: where you have a dual presence, where you appear only through paid advertising, and where you rank organically without any ad coverage. This overview is the quickest starting point for making better decisions on both fronts.
2. Work from a single list of keywords, categorised by intent. Don’t create a separate list for SEO and another for Ads; instead, use a single analysis to distinguish between informational, commercial and transactional intent. Then, for each keyword, assign a primary page and a primary channel. Long-tail informational searches go to SEO, whilst comparison and purchase-related searches usually go to SEA.
3. Let SEA cover what SEO doesn’t yet deliver, and scale back as soon as organic traffic takes over. Check every quarter which search terms you’re ranking in the top three for, and adjust your bidding strategy accordingly. The budget freed up should be allocated to keywords where your organic performance is still weak. This will reduce your total acquisition cost whilst maintaining your visibility.
4. Test your ad copy and reuse the most effective ones. An advert variant with a high click-through rate tells you exactly which message resonates with your audience. Incorporate that wording into your page titles and meta descriptions. It works the other way round too: use the short answers you write for your FAQs as sitelinks or structured snippets in your campaigns.
5. Focus your advertising budget on commercial and transactional intent. That’s where the impact of AI Overviews is lowest and the return per click is highest. You should direct informative search queries to your content, which already delivers the highest return per euro invested in that area anyway.

How much the combination costs and how the distribution shifts

For a serious SEA campaign in the Netherlands, you should expect a media budget of at least €1,500 to €2,500 per month, plus management fees if you outsource it. Click prices vary widely: for standard keywords, you’ll often pay between €0.50 and €5.00, whilst competitive B2B terms can cost up to €25.00 per click. For SEO, the investment is usually between €1,500 and €4,000 per month for technical optimisation, content and link building, and these costs are spread over 12 to 24 months as organic traffic continues to grow. The full breakdown of costs, including what you pay for management and how to build a budget, can be found in how much Google Ads costs.

The split between the two channels is not a fixed figure but a curve. A commonly used rule of thumb for an SME without an organic foundation is: year one at 70% SEA and 30% SEO, year two moving towards 50/50, and year three moving towards 30% SEA and 70% SEO. In the first year, SEO generates very little traffic, so visibility relies on adverts. As organic rankings improve, the balance shifts.

Two points to note, as a curve like this is quickly interpreted as a rule. Firstly, SEO also costs money: content, technical aspects and link building are genuine expenses that belong in the same budget, even if they do not appear as click costs. Secondly, competitive markets often require a permanent advertising budget – even if you’re performing strongly organically – simply to keep out competitors bidding on your brand name. That item will never disappear entirely from your budget.

If you’re on a tight budget, pay close attention to your bidding strategy. Smart Bidding needs data to work: Google recommends around thirty conversions in the previous thirty days for Target CPA before the algorithm has learnt enough, and the same order of magnitude applies to Performance Max. If you’re below that threshold, ‘Maximise Clicks’ or a manually optimised campaign with a tight keyword profile is often more stable. In the meantime, build up your conversion volume by broadening your conversion definition, for example by tracking both phone calls and forms.

How to measure it accurately

Someone clicks on your advert, has a look around and leaves. Three days later, that same person returns via an organic search result and then requests a quote. Do you attribute that conversion to SEA or to SEO? In the conversion path reports in Google Analytics 4, you can see exactly these kinds of paths, and they are the rule rather than the exception. Anyone who looks only at the final click will consistently draw the wrong conclusion about which channel is effective.

You should therefore pay close attention to your attribution model. Standard last-click attribution systematically disadvantages SEO, as organic traffic often occurs early in the customer journey and the conversion is subsequently attributed to a different channel. A data-driven attribution model provides a fairer picture of each channel’s contribution. How to set up this measurement framework and which settings matter is explained in the A comprehensive guide to Google Analytics 4.

Next, focus on shared goals rather than channel-specific figures. A useful KPI is Total Search: the total non-brand search traffic and total revenue from search engines, regardless of whether it came from paid or organic sources. This prevents two teams from cancelling each other’s results out in the reporting. Consolidate the data from both channels into a single dashboard, for example in Looker Studio, so that you can spot patterns that would otherwise remain hidden in two separate reports.

And measure at the level where decisions are made. It’s not the cost per click, but the cost per lead and per customer that determines whether your budget is on track. A €15.00 click that brings in one customer with a customer lifetime value of €2,000 is an excellent investment. A click costing fifty cents that never converts is a waste of money.

The mistakes that are quietly eating away at your budget

Ignore keyword cannibalism. Cannibalisation occurs when several pages on your site compete for the same keyword. Google then cannot determine which page is the most relevant, and both pages perform worse than a single strong page would have done. Resolve this by designating one primary page per keyword and aligning your internal links, headings and content accordingly. Search Console helps you identify these duplicates: if two URLs are alternating in the results for the same search query, you’ve found a case of cannibalism. The same principle applies to a combination of channels: without a clear division of roles for each keyword, you’ll end up competing against your own organic ranking.

Carry on advertising where you’re already at the top organically. If you’re already in the top organic result, the added value of an advert appearing above it is limited, and you’ll be paying for clicks you were getting anyway. There are exceptions – your brand name being the main one – but check this on a term-by-term basis rather than leaving it on everywhere.

Let Performance Max do its thing. Performance Max tends to allocate budget to search terms where you’re already performing well organically, simply because those conversions appear to be cost-effective. Without exclusions and without aligning with your organic data, you’ll end up buying traffic you already had. Set up negative keywords and keep an eye on your search terms reports.

Managing SEO and SEA in separate silos. If the content team doesn’t know which search terms are converting in Ads, and the campaign manager has no idea which pages are already performing well organically, they’ll end up working against each other. The greatest benefit of this collaboration lies precisely in that exchange.

Creating plain landing pages for your campaigns. A separate, thin page dedicated solely to adverts does not build any organic value and usually scores poorly in terms of the landing page experience as well. Create one strong page that serves both channels.

Treat SEO as a project rather than a process. Algorithm updates, new competitors and changing search behaviour require ongoing attention. An audit that you carry out once and then file away won’t make any difference.

Believing in guarantees. Be sceptical of agencies that promise fixed top rankings or the number one spot within three months based on generic search terms. Nobody can guarantee a ranking; Google says so itself. You can find out what you should look for when choosing an agency in Choosing an SEO agency.

This is how we go about it

We manage SEO and Google Ads as part of a single strategy, rather than through two separate departments. In practice, this means that new campaigns usually start with adverts to quickly gather data and achieve initial visibility, whilst the technical and content foundations are being laid. The conversion data from Ads then determines which content is prioritised. After three to six months, we reallocate budget and resources based on the actual results: which rankings proved achievable, which keywords need to remain active, and where the biggest gaps lie. No silo thinking, just one goal.