SEO vs. SEM: Comparing Techniques, Costs & Impact

SEO and SEM both target traffic from search engine results pages, but in different ways. While SEO focuses on optimizing content to organically rank on SERPs, SEM uses a mixed approach of organic content and PPC ads.

April 17, 2024
Written by
Nate Matherson
Reviewed by
Charles Purdy

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The main difference between search engine optimization (SEO) and search engine marketing (SEM) is that SEO focuses on improving organic search results, to attract organic traffic, and SEM combines targeting organic traffic and using paid strategies to reach searchers.

Here’s a quick recap of what both terms mean:

  • SEO involves optimizing website content to rank for specific keywords.
  • SEM uses SEO alongside paid search ads (known as pay-per-click — or PPC — ads).

I fell in love with SEO early in my career. I was working for a small startup with a shoestring budget, and we simply didn’t have the money for paid ads, so we focused on organically improving our search rankings. The more established we became, the more we could invest in PPC ads. Running PPC ads in tandem with our original organic SEO efforts led to huge growth. I’m now a keen advocate for using the two strategies together.

What Is SEO?

SEO targets the organic section of search engine results pages (SERPs). This includes the snippet spot, the People Also Ask section and the listings below the sponsored results.

But most companies don’t want to land in any old spot on a SERP — they want their pages to be one of the top three organic results, because these are the pages that get the most clicks. The top organic spot enjoys 27.6% of clicks, the second spot gets 15.8%, and the third spot gets 11.0% of clicks. The numbers dwindle from there.  

These click-through rates are far higher than they are for the paid ads (even though paid ads show up right at the top of the search results). This is because searchers are savvy and would rather click through to a page that has “earned” their attention than go to a page that has paid for it.

The downside is that organic SEO takes time.

It typically takes at least 30 days to start ranking in search results, let alone to land in one of those coveted top spots. Plus, the competition is fierce. Everyone wants a piece of the pie, so competitive keywords can be difficult — if not impossible — to rank well for if you don’t have an established domain. And creating well-optimized content takes time. You not only have to run keyword research, develop briefs, write the content, and run each page through an optimization tool, but you also need to secure backlinks to give your content a chance at ranking.

The Different Types of SEO

There’s no one-size-fits-all formula for SEO. There are different types of SEO and different factors that influence search engine rankings.

Here are the most common types of SEO.

1. Content-Led

Also known as traditional SEO, content-led SEO is the type we talk about the most. It involves creating high-quality, keyword-optimized blog posts, articles, downloads, and webpages to rank well on SERPs.

A typical content-led SEO process might look something like this:

  • Research relevant industry keywords.
  • Create a content plan to target high-volume, low-competition keywords.
  • Write, optimize, and publish content around these keywords.
  • Use internal linking to develop authority related to main keywords.

Content-led SEO requires effort. You need to invest heavily in content creation — both time and resources — to see results.

2. Product-Led SEO

Product-led SEO looks similar to a content-led SEO at first glance, but instead of putting content at the center of operations, it focuses on the product.

The idea is to create webpages around product features and user experience — think Airbnb, and how it ranks for individual property listings. The product is the content (in other words, the search term “best places to stay in New York” might lead to a page of Airbnb listings in New York).

3. Programmatic SEO

Programmatic SEO involves the automatic (or nearly automatic) creation of many keyword-targeted pages using internal data — usually on a very large scale. Think Tripadvisor, which has a page for almost every travel-related search term. Anyone who searches for “top things to do in [city]” will likely be served a Tripadvisor page generated from top reviews and ratings. Nobody has “written” this page. Instead, it’s an amalgamation of key data points that can change over time.

Factors That Influence Search Engine Rankings

Google is constantly moving the goalposts, so a page that ranks well today might not rank well next week or next month. The myriad ranking criteria (and how they are weighted) are always changing, so you can’t sit back and relax for even a moment — even if one of your webpages has reached that elusive top spot.

So, what are these factors?

  • High-quality content: High-ranking content is well-written and engaging and demonstrates unique expertise.
  • Search intent: Content needs to align with what searchers want. The four main intent categories are transactional, navigational, commercial, and informational.
  • User experience: Search engines want to provide the best experience possible for searchers, so content that ranks well needs to be clear and easy to navigate.

In addition to creating compelling content and ensuring that users have a good experience, there are a handful of tactics that can increase your chances of search engine success.

Keyword Research

Use a keyword research tool like Ahrefs, Semrush, or Positional to find relevant keywords. Terms with a high search volume and a low difficulty score are the easiest to rank for, but you should use a mix of keywords to create a comprehensive resource. The more relevant keywords you cover, the likelier Google is to deem you an authority on the topic, which can increase your overall rankings.

Technical SEO

Employing technical SEO best practices ensures that your website meets the technical requirements of modern search engines. You can have the best content in the world, but you might struggle to rank well if your site loads slowly or your sitemap is a mess.

On-Page SEO

On-page SEO refers to the tactics you employ on each page to increase the page’s chances of ranking. This includes adding keywords to your page titles and meta descriptions, structuring your content well, and implementing internal linking best practices.


Google uses the number and quality of a page’s backlinks to determine the page’s usefulness. The more high-quality links a page has pointing at it, the likelier it is to be considered a top resource. Securing links from relevant, high-authority sites can help you rise on SERPs. There are many different ways to build backlinks, including by guest blogging and by creating link bait.

What Is PPC?

PPC is a model of advertising where the advertiser pays every time someone clicks on their link. Google Ads is the most popular PPC platform, but it’s not the only one. You can also run PPC ads on Bing (Microsoft Ads) and social media platforms like Instagram, LinkedIn, and X (formerly Twitter). When we talk about SEM, though, we’re mostly referring to PPC ads that show up on SERPs and are identified by the “Sponsored” tag.

The most obvious benefit of PPC ads is that you can secure a top spot on SERPs — but that spot comes at a price. While organically climbing to the top spot is a marathon, PPC ads are more of a sprint. The more you pay, the easier it is to win the top spot. But the click-through rates aren’t nearly as good as they are for organic content. The ad spot generates only 2.1% of click-throughs even though it’s right at the top. It is worth noting that CTR for the ad spots can vary pretty dramatically depending on the search query. Sistrix, for example, reports significantly higher CTRs on Google Ads.

What You Need to Know About Running PPC Ads

PPC is a pay-to-play search strategy, but there are still some important concepts to grasp before you get started.

  • Keyword research: You still need to research the keywords people are typing into search engines and map those to the primary search intent.
  • Costs: PPC ads work on a bidding system — the more you “bid” on a keyword, the likelier it is that you’ll rank for it. The price can get eye-wateringly high for competitive keywords, so it’s important to set a maximum cost and be realistic with the keywords you target.
  • Creating ads: You need to create a title for your ads and a short introductory sentence that will compel people to click through. Without an enticing title, you’ll struggle to get the clicks you want.
  • Audience targeting: The great thing about PPC ads is you can home in on a specific audience. For best results, make sure you understand exactly who you want to reach and have solid data points to work from.

SEO vs. SEM: How Long Does It Take?

The reason SEO and PPC work well in tandem is because they cover all the bases — when you invest in SEO, you’re playing the long game. It can take at least a month to even begin to rank for your chosen keywords, let alone secure one of the top spots. And this is assuming that you’re targeting low-competition keywords. It can take three to six months to see results for highly competitive search terms.

However, once you’re ranking well, you can reap the rewards for months and years to come, as long as you continue to implement good SEO practices.

SEM can fast-track you to the top. If you have the budget, you can set up a PPC ad in minutes. But it’s the testing and continuous optimization that proves time-consuming. It’s unlikely that the very first ad you release will be your best try, so it’s important to test, measure, and tweak your PPC ads until you find a formula that works well.

How Much Does SEO Cost?

SEO is a long-term investment (remember, it’s a marathon). And, while it may seem more cost-effective than an SEM PPC strategy, it’s not free. You still need to put time, resources, and money into creating content and webpages.

The costs will vary depending on your setup. Writing content in-house might be cheaper than hiring freelance writers, but if you need to hire a dedicated person to focus on content creation, it can become a costly expense depending on the level you want to hire at.

Our previous research found that a piece of content costs anywhere from $150 to $1,200, depending on its complexity. If you have big plans for, say, 10 pieces of content a month, you could be looking at a $12,000 monthly investment. However, once you’ve made the initial investment, your SEO channel can be an incredibly valuable asset to your business, as it will keep bringing in traffic months (and even years) later.

How Much Does PPC Cost?

PPC costs vary depending on the industry, and some industries can be expensive. The average cost-per-click (CPC) across all industries is $2.69, but it can be as high as $6.75 in the legal industry and $6.40 in consumer services.

The consumer finance space is particularly expensive — when I began working in SEO, I couldn’t invest in PPC because the costs were too high. However, prices can be very manageable (and even a pleasant surprise) in other industries. For example, PPC costs can be as low as $1.16 in e-commerce and $1.53 for travel and hospitality.

Which Is Better: SEO or PPC?

In short, it depends.

How much time do you have? How much budget do you have? Can you do both? Many of our customers are running both PPC campaigns and SEO campaigns targeting the same keywords and are getting great results.

Often, the PPC and SEO teams are best friends and share insights. For example, if a certain keyword is performing well on PPC ads from a conversion standpoint, you might decide to focus on it from an SEO standpoint, too. Using one strategy to enlighten the other seems to work well, particularly if you’re in a competitive industry.

Using only SEO in a competitive industry can be hard work. It’s going to take longer to rank than it would in a niche space — in that case, SEO can be a quick way to rank well. It’s the same for PPC campaigns. The CPC might be expensive in one industry but not another, so check where your industry sits in terms of costs and competitiveness.

The best strategy to use depends on your goals, too. If you’re targeting keywords with direct buying intent, PPC can maximize your chance of conversions. If you’re targeting keywords with an informational intent or that sit at the top or middle of the funnel, SEO might be a better bet.

To break it down:

  • SEO is better if you have a small budget and want to (or need to) play the long game.
  • PPC is better if you want to rank right now for transactional keywords (and have a decent budget).

Ideally, you’d use both in tandem. While you’re building up your SEO channel, you can invest in PPC ads to generate quick clicks and immediate sales.

Final Thoughts

SEO and SEM both target traffic from SERPs, but in different ways. While SEO focuses on optimizing content to organically rank on SERPs, SEM uses a mixed approach of organic content and PPC ads.

Both channels can boost rankings, increase visibility, and secure more conversions, but they work in different ways. SEO is a long game that involves creating high-quality content and building out a comprehensive industry resource, whereas SEM and PPC ads can quickly generate traffic if you bid for high-volume, transactional keywords.

I’ll often recommend building out both channels and using them together. Focus on growing your organic presence in search results with strategic keyword-focused content while also investing in ads to convert low-hanging fruit.

Most importantly, choose the channel that suits your needs right now — knowing that your needs may change as your business grows. If you’re in a niche industry or just starting out, SEO can be a relatively cost-effective way to build your authority and start ranking on SERPs. When you have the budget to invest in ads, you can add a PPC channel to your efforts to target consumers at every stage of the funnel.

Nate Matherson
Co-founder & CEO of Positional

Nate Matherson is the Co-founder & CEO of Positional. An experienced entrepreneur and technologist, he has founded multiple venture-backed companies and is a two-time Y Combinator Alum. Throughout Nate's career, he has built and scaled content marketing channels to hundreds of thousands of visitors per month for companies in both B2C (ex financial products, insurance) as well as B2B SaaS. Nate is also an active angel investor with investments in 45+ companies.

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