SEO, SEA, and SEM: key differences and how to make them work together

If you’re taking your first steps in digital marketing, it’s normal to feel overwhelmed by the many acronyms and technical terms. But don’t worry, we’re here to help! 

This article will explain three essential concepts for any web marketing strategy: SEO, SEA, and SEM. You’ll learn the differences between them, what each is used for, and how to make them work together to boost your digital business. No more waiting—let’s dive in ASAP! 

What SEO, SEA, and SEM are and the differences between them 

Both SEO and SEA focus on driving traffic to a website via search engines like Google, Bing, and Yahoo!, but each approaches this goal from a different angle: SEO focuses on organic traffic, while SEA relies on paid advertising. SEM is the combination of both strategies. 

Let’s now take a closer look at each one. 

What is SEO? 

SEO stands for Search Engine Optimisation, and it refers to strategies for attracting organic traffic to a website through search engines like Google. 

When we talk about ‘organic traffic’, we mean visitors who arrive at a website naturally, without the need to pay for ads to appear in search results. To achieve organic traffic, it’s necessary to optimise different aspects of a website so that search engines consider it relevant for specific topics and rank it among the top results. 

Google, the world’s most used search engine, explains that SEO “is about helping search engines understand your content, and helping users find your site and make a decision about whether they should visit your site through a search engine”. 

SEO optimisation actions include: 

• Using on-site content that contains the terms or keywords users search for. 
• Creating high-quality, relevant content for users. 
• Improving the site structure so search engines can easily understand it. 
• Optimising the loading speed. 
• Preserving website security. 
• Acquiring external links (backlinks) that point to your website. 

These are just a few of the most essential SEO actions. To learn more, check out our guide on the 25 best SEO tips. 

What is SEA? 

SEA stands for Search Engine Advertising and refers to all digital marketing strategies that use paid ads to appear in search engine results. 

When you search on Google or Yahoo!, you’ve probably noticed that the first links you see are labelled “Ad” or “Sponsored”, and they appear before the organic results. This means the website has paid the search engine to appear in the top positions for queries related to its products or services. 

The most common model is Pay Per Click (PPC), where the advertiser pays only when a user clicks on their ad. Unlike SEO, which usually takes more time to climb the rankings, SEA delivers nearly instant results. The trade-off is your visibility only lasts as long as the campaign is active and your budget allows. 

Like SEO, choosing the right keywords, the ones your target audience are truly searching for, is the foundation for connecting with future visitors. The downside is that high-traffic keywords tend to be the most competitive and expensive.  

Additionally, an optimised landing page is crucial. Attracting clicks is pointless if the page your visitors land on doesn’t convert those visits into customers. We’ll talk more about this later. 

What is SEM? 

Finally, let’s take a look at SEM, which stands for Search Engine Marketing. In simple terms, SEO + SEA = SEM. 

That means that SEM is a broader concept that covers all digital marketing strategies aimed at gaining visibility on search engines. 

Sometimes, people mistakenly use SEM as a synonym for paid ad campaigns. The reality is that SEM covers both advertising actions and optimisation techniques designed to appear in the top organic search results. That’s why it’s important to consider SEM as an integrated strategy that combines both approaches. 

The following section will explore how SEO and SEA can work together to maximise results. 

How to integrate SEO and SEA into your SEM strategy 

As mentioned, an effective SEM strategy combines SEO and SEA actions. The key is to balance these two approaches, treating them as members of the same team. 

Combining long-term and short-term goals 

SEO and SEA don’t compete. Rather, they complement each other. SEO focuses on building authority and relevance around specific topics and keywords, working long-term to help your website rank organically. In contrast, SEA lets you achieve immediate results and take advantage of spontaneous opportunities through paid ads. 

For example, you’ve created an online shop specialising in running shoes and accessories. At first, your website probably won’t appear among Google’s top organic results. Your job is to optimise your site using SEO best practices. For instance, you can get started by writing product descriptions with relevant keywords or creating blog posts that answer the most common questions your target audience might search for. You could also reach out to sports-related websites and secure backlinks.  

These actions will help you build lasting authority over time. 

In parallel, you can launch a SEA campaign to immediately give your store visibility and drive sales from day one that will help you recover your initial investment. For example, you could place ads for the keyword “cheap running shoes” to attract users who are ready to buy.  

This way, you can drive traffic from the start while working on SEO for e-commerce to strengthen your ranking over time. 

Prioritising your strategy based on goals and stages 

Following this logic, before prioritising one approach over another within your SEM strategy, it’s essential to define your short- and long-term goals clearly. 

Want to boost your seasonal sales? A well-timed SEA campaign can help you capture customers at precisely the right moment. Or if your online shop focuses on camping gear and outdoor activities, a few months before summer would be the ideal time to invest in ads targeting related keywords. 

On the other hand, if your goal is to build a strong, sustainable brand presence, your efforts should be focused on SEO. A proven approach is to create a business blog with high-quality, relevant content in your area of expertise.  

If the information you provide is genuinely helpful and solves real user questions, Google and other search engines will reward you by positioning your website as a reference in the sector. 

In short, if you’re launching a new project or promoting a limited-time offer, SEA will help you get traffic fast. Meanwhile, SEO is a long-term investment that maintains and improves that presence. 

Keywords and landing pages: the common ground for SEO and SEA 

Two key elements demand your attention to create an effective SEM strategy, as they form the foundation for SEO and SEA. We’re talking about keywords and landing pages. 

Let’s break down each one: 

Keywords 

Keywords help you understand how users search for information via search engines. When you conduct keyword research, you gather essential data such as which terms are used in different regions, semantic variations, user intent, and monthly search volumes. 

This information is extremely valuable for both SEO and SEM efforts. For organic searches, it gives you a strong data foundation to produce your website content. 

Let’s go back to the running store example: if your research reveals that many users search for “how to choose running shoes,” you can create dedicated content around that keyword. For instance, you could write a blog post explaining the factors to consider when purchasing running shoes. Effective SEO copywriting allows you to integrate keywords smoothly, without forcing them into the text. 

For SEA, keywords are the cornerstone for deciding when and where your ad will appear. When you set up a campaign, you select a list of keywords. Whenever a user types that keyword or a similar one into the search engine, your ad will compete in an auction against other advertisers who’ve selected the same keyword. You can adjust the match type to show your ad only for exact matches or allow for related search terms. 

Landing pages

Whether a user lands on your page via a paid ad or through an organic result, the landing page must be well-optimised. 

Imagine a user searches for “cheap running shoes” and clicks on your site, whether through an ad or a search result, but the page is slow to load, disorganised, or redirects to a football shoes category instead. That visitor will quickly leave, and you’ll lose a valuable conversion opportunity. 

In this sense, the landing page’s mission is to turn casual visitors into customers. Our landing page guide offers tips on how to optimise them. To summarise the guide, a great landing page should be: 

• Clear and focused on a single conversion goal. 
• Straightforward, with a visible value proposition right from the start. 
• Free of distractions, avoiding unnecessary menus, banners, and links. 
• Visually appealing. 
• Equipped with clear, visible, and well-placed calls to action (CTAs). 
• Have only simple forms that ask only for essential information. 
• Easy to track and analyse to optimise your marketing campaigns. 

SEM: an integrated strategy 

As we’ve seen, understanding the differences between SEO and SEA is essential to designing a solid and efficient SEM marketing strategy. Knowing how to combine these tools will allow you to attract traffic at different stages, through various formats, and build a long-lasting online presence. 

That said, whether you focus on organic positioning or invest in paid campaigns, the work doesn’t end when you publish your content or activate your ads.  

Constant optimisation is key to adapting to changes in search engine algorithms, search trends, and user behaviour. Analysing results, adjusting keywords, improving your landing pages, and refining your campaigns will help you keep your strategy in top shape.