What Is The Difference Between SEO And SEM?

Often Search Engine Optimisation (SEO) and Search Engine Marketing (SEM) are used interchangeably causing confusion but what are the real differences?


SEO increases the number of visitors to your website by optimising your content. SEM uses organic (free) techniques and paid advertising to send more people to your content.

Generally, SEO is a component or activity of the larger process of SEM.

What Is SEO?

Search Engine Optimisation is a process to increase the number of visitors to a website by increasing the visibility of the site content in search engine results pages (SERPS).

Or, in other words, increasing the website ranking for specific search terms.

What Is Involved In Performing SEO?

There are lots of different components that make up the SEO process which are generally split into two activities

On-Page SEO

Optimising the content on your own website.

  • Writing lots of natural reading, quality content articles
  • Optimising content for specific keywords
  • Optimising the metadata on the content for a specified keyword; image alt tags, titles, headers, meta descriptions etc.
  • Optimising page loading speed (faster loading)
  • Sharing content on social media
  • Easy to read and keyword specific article URLs
  • + lots more!

Off-Page SEO

The actions taken outside of your own website to impact your rankings within search engine results pages (SERPS).

  • Seeking high-quality backlinks to your website content
  • Engaging with social media influencers
  • Social bookmarking
  • Guest blogging
  • + lots more!

What Is SEM?

Wikipedia describes Search Engine Marketing (SEM) as “a form of Internet marketing that involves the promotion of websites by increasing their visibility in search engine results pages (SERPs) primarily through paid advertising.

What Is Involved In Performing SEM?

As I briefly mentioned at the start of the article, SEM includes a lot of SEO – in fact, most of your Search Engine Marketing will be comprised of the Search Engine Optimisation component.

In addition to SEO which involves mostly organic (free) components, SEM is the addition of paid advertising to the process.

Paid advertising can include:

  • Google Pay Per Click (PPC) adverts
  • Facebook adverts
  • LinkedIn adverts
  • Radio, TV and other media advertising
  • +lots more

Pretty much any form of paid advertising is included in SEM – you get the point right?

What Is the Main Difference Between SEO and SEM?


SEO is generally free (except for your time) and SEM is generally in the form of paid advertising and organic (free) processes (the SEO part).

Which One Is Best?

Both are equally important.

Because SEO is actually part of the bigger SEM process you should consider how to combine both effectively to make sure you are getting the best exposure to your content that you can.

Most people and companies will start off performing some level of SEO, even if they don’t understand or formalise the process.

Adding content to your company site in the form of regular blog posts and sharing them on social media are crucial components of SEO, even if you don’t call it that.

Organic (free) on-page and off-page SEO will take time, perhaps 6+ months to start yielding any significant change in your SERPs so be prepared for a long-haul journey, or fast-track and pay somebody to do it for you.

If you are a new company and need quick visibility and traffic, then paid advertising is a good choice as organic SEO takes many months of work.

You should not be throwing any money at advertising without understanding your target audience and where they are in the “buying pyramid” – more on that in another post!

All advertising is not equal and you need to understand or pay a company that understands how advertising works on different platforms.

Book a free 15 minute call with me to discuss your business’ SEM needs today.

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Wil is a dad, WordPress consultant, WordPress developer, business coach and mentor. He co-organizes the WordPress Sydney meetup group and has been on the organising committee for WordCamp Sydney since 2014. He speaks at many special events and contributes to the WordPress open source project. His likes are chillies, craft beer and electrogravitics.