SEO Vs SEM: What’s The Difference?

seo vs sem

If you’re looking to use online marketing to develop your business, then you may have heard of SEO vs SEM.

As marketing grows and changes over time, new terms and acronyms emerge. This can be quite confusing for people outside the world of internet marketing. Sometimes even marketers themselves get confused.

Two acronyms that are often referred to is SEO vs SEM. But what are they? And, What’s the difference between the two?

It’s important to know the difference between SEO vs SEM so that you can determine how to allocate funds to your marketing strategy.

Both concepts can be difficult to get your head around if you’re new to online marketing. SEO and SEM are often used interchangeably, which further adds to the confusion.

SEO stands for Search Engine Optimization.

While, SEM means Search Engine Marketing, also known as Search marketing.

However, SEO is part of SEM.

SEO vs SEM are both strategies to increase your visibility on search engines. Improved visibility will attract more customers to your website. SEO and SEM do this by doing what search engines want.

The beauty of both SEO and SEM is that it is targeted marketing!

That means when someone searches a product or service that your business provides, with a better ranking you more likely to convert their search into a click on your website.

This is hugely valuable for your business because it’s been shown that 91% of internet users go on search engines.

Before we explore the differences between the SEO and SEM, we need to be clear on our definitions.

What is SEO?

SEO is a strategy used in online marketing to optimize your website for search engines. This is achieved by getting, what is known as, free traffic.

In other words, the search engines can make sense of your website better than other websites. This increases the probability that your ranking will be higher in SERPS. Another acronym, I know. SERPS stands for Search Engine Results Pages.

The SEO industry – yes, there’s a whole industry around this stuff – is always adapting to new trends and developments made to Google’s algorithm. The algorithm is the name of the complex set of calculations that determine the search results.

This is why it’s important to keep up to date on how your online marketing strategy is doing. If you’re not careful, your website could drop a dozen pages lower in SERPS.

Ok, now you understand what SEO is, we can move on to the two different aspects of SEO. There’s on-site SEO and off-site SEO (otherwise known as on-page and off-page).

While many things are always changing in the industry, on-site and off-site SEO stay the same.

On-site SEO is techniques to use on your blog or website to make it search engine friendly.

This includes optimizing titles and headings with selected keywords, effective use of images and well-formatted URLS. And much, much more.

Did you know you could get “votes” from other websites?

By getting “votes” from other websites search engines are more likely to trust you. Votes from other sites mean a higher SEO ranking. This is called Off-site SEO.

How do you get votes from other websites?

Whenever there is a link from another website to your website, this acts as a vote of approval. This is why off-site SEO is also known as link building.

However, it is not only the quantity of links from other sites but the quality of the other website. That means authoritative websites.  

What is SEM?

Now let’s talk about SEM.

Just to be clear. While SEO is a part of SEM, SEM is one part of overall internet marketing. There are many other strategies and techniques to internet marketing. Of course, we’re just discussing SEO vs SEM here.

The SEM process can be achieved through free traffic, which is SEO, or paid traffic. That’s paid search engine advertising or PSA.

In recent times, SEM has started to be referred to as only PSA. This makes it all more confusing. For our purposes, we’ll understand SEM as only paid advertising.

PSA is simply buying space and exposure on the results page of a search engine. You’re paying to rank higher than others on search engines.

There are many advertising agencies that offer these services. Often you don’t pay for the ranking, but rather every click on your website or advert. This is known as Pay per click. That’s the acronym PPC.

Twitter, Facebook, and other social media websites are increasingly breaking into this market by developing their advertising platforms. However, online traffic from search engines is still a better return on your investment.  


So, what’s the difference?

While SEO is often understood as part of SEM. You should never use these terms interchangeably. Although they are related, they are not the same.

It’s easy to understand the two concepts as free (SEO) and paid and sometimes also free (SEM) marketing.

Which is better, SEO vs SEM?

Marketers are often arguing with each other about which is better SEO vs SEM.

It makes sense to say that SEM cannot work effectively without SEO. SEO can really lay the foundations for a successful SEM campaign.

If you don’t use optimized content, your SEM activities are probably going to fail.

But, SEO is a long term process and takes time to build up. It doesn’t happen overnight. In the long run, SEO is much more cost effective and allows you develop search creditability.

On the other hand, if you are trying to get some traffic for your first website and you need it to be effective immediately, then SEM could be better. You may not have time to develop your SEO over time, in that case, a strategic SEM campaign could be your best option.

It’s important not to rely on SEM without SEO in the long run though.


It’s important to consider the specific needs of your business. Get in touch with us at See All Media to get a quote on how we can help your business with SEO, web design or Content Marketing. 

You can also check out our blog and our free SEO audit tool.