SEO Versus SEM: What Are The Main Differences


As the world of marketing becomes more technical, the more obscure the language can get. It’s easy to get one term mixed up with another because they have similar acronyms or they just sound the same in general.

Two of the main culprits are SEO (search engine optimization) and SEM (search engine marketing). They are used interchangeably by marketers but what some don’t realize is that they have different properties.

While they can work together, it’s important to understand how and why they are different so you know when and where to apply each technique.

This article will describe the main differences between SEO and SEM and show you how to use them both to achieve the best results.

What Is The Main Difference Between SEO and SEM?

SEO has long been thought of as a branch of SEM. However, in 2019, SEM is mostly referred to as paid search, while SEO deals with organic search only.

Search Engine Land describes search engine marketing as “the process of gaining website traffic by purchasing ads on search engines.” On the other hand, they describe search engine optimization as “the process of getting traffic from free, organic, editorial or natural search results.”

From these different definitions, the main difference is clear. Nevertheless, they are both still excellent tools to help market and grow your business.


According to Digital Authority Partners, the primary goal of SEO is to drive the most qualified traffic to your site as possible.

With Google always updating their algorithms to provide the most relevant results to searchers, SEO marketers must be ready to adapt their methods.

But no matter how much the algorithms get tweaked, there are some things about SEO that will always remain the same: on-page SEO and off-page SEO.

On-page SEO deals with things that can be controlled by the user themselves:

  • Formatting on-page content correctly for Google, such as title tags, metadata, headings and alt tags on images;
  • Keyword research to make the page discoverable for search;
  • Content that includes the page’s keywords;
  • Ensuring that the page loads quickly;
  • Simple but keyword effective page URLs.

Use these techniques to help create high-quality content that visitors are more likely to engage with.

Off-page SEO requires doing as much as possible away from the site to influence traffic:

  • Link building campaigns to obtain backlinks from authority websites. This has a big impact on search rankings in Google;
  • Social media engagement;
  • Featuring on social bookmarking sites;
  • Directory submission.

The key to off-page SEO is creating high-quality content. When content provides a lot of value to a reader, it’s more likely to be shared with friends or colleagues on social media or used as a resource from other blog posts or websites.

This helps to raise your own website’s authority in the field and, over time, will increase rankings in Google’s search results, leading to more traffic and, ultimately, more conversions.


Search engine marketing is the process of being visible to searchers through paid advertising. This method is commonly known as pay-per-click (PPC – yet another acronym) but there are plenty of other names for it.

The purpose of PPC is to target customers through ads relevant to the keywords users are searching for. After a search is made, PPC ads appear next to the highest organic ranking search results.

Businesses invest in PPC because they aren’t ranking on the first page of Google. Therefore, to increase the visibility of their website, they invest in ads to attract a click from a searcher. Considering that Google is the most popular search engine, Adwords is then, by inheritance, the most popular platform for paid ads.

Successful SEM techniques include:

  • Creating a buyer persona in order to target a specific audience
  • Using ad groups that contain variations of the primary keyword
  • Including these keywords in the ad copy
  • Keeping an eye on important PPC metrics such as impressions, clicks, click through rate and the average cost per click

While PPC is great for getting your website in the eyes of your customers, it comes at a price. You need to have a budget in place before investing in PPC campaigns.

When To Use SEM

Since it’s unlikely they’ll be ranking on the first page of Google’s search pages anytime soon, new businesses would benefit greatly from the increased visibility and traffic SEM can provide.

As traffic and rankings increase, start building up organic search credibility with consistent high-quality content. This will prevent you from relying on SEM for long-term success, blowing through your budget as keywords become more and more expensive.

Plus, visitors will want great content to engage with once they land on your page.

What’s Better? SEO or SEM?

There are arguments to be made on both sides. Both SEO and SEM can provide a lot of value to your business and, if you can afford it, both should be used as part of the overall inbound marketing strategy.

But you cannot have good SEM without strong SEO.

Poor-quality landing pages and blog posts are not something Google and search engines want to show searchers. This will have an adverse effect on SEM, resulting in poor ROI and harming organic rankings in the process.

SEO ensures that website content is optimized for their search so when they land on a page, they are sure that the content is valuable and worth the read. High-quality content is key to achieving social shares becoming link-worthy to other sites.

It also costs significantly less over SEM in the long run and builds the reputation of the brand too. After all, the number one result in Google must be doing a lot of things right, otherwise visitors would choose another result.


In short, SEO is organic search and SEM is paid search. Both can provide your business with what it needs to increase traffic and conversions. All businesses should use SEO but it’s important you know why your business would benefit from SEO and SEM before investing in paid search.