There’s a debate taking place in the marketing world about the nature of search engine optimization (SEO). Is it really a distinct marketing channel? More importantly, has it become such a business necessity that it’s unnecessary to measure its return on investment?

While the first question understandably interests marketers, it’s not of much interest to businesses, especially small businesses, looking to allocate precious marketing dollars. The return on SEO is where the rubber hits the road.

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So is SEO a necessity? Or is it a marketing expenditure to be judged on the basis of ROI?

It’s both.

SEO is, in fact, necessary in today’s marketplace. Potential customers do not use the phone book. They use a computer, smartphone or tablet to find what they need. Any business with a website needs to be visible when a potential customer uses an electronic device to search for its product or service.

But it’s also necessary to have people to provide that product or service to a customer. Businesses are certainly interested in employee productivity, and use various means to measure it. Nearly every expenditure has an ROI, either in terms of reducing cost or increasing revenue. SEO is no different.

These are the methods we use to measure SEO ROI.

The first measure is organic website traffic, and whether it is increasing or decreasing over time.

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The second is rankings, where a site comes up in a search. That’s actually a rather difficult measure to determine. But there are places to obtain it. Third-party companies such as Moz.com provide ranking data and can demonstrate how those rankings change over time. Even Google provides this information to webmasters.

The third measure is what we call “entrances.” This boils down to how many of a site’s pages are receiving organic referrals. Of course, the more pages, the higher the return.

Finally, the measure that means the most to most business owners is leads, prospective customers who have expressed interest in your product or service but not yet purchased. In most cases they express that interest by completing a web form or calling your business. How many web leads? How many phone calls? And, critically, what is the cost per lead?

If lead measurement is missing from the equation, the first three metrics do not matter. If the leads don’t meet expectations, and the price per lead is not competitive with other marketing channels, then the ROI is not sufficient.

Does that mean a business shouldn’t invest in SEO? No. But it will certainly influence the amount invested.

SEO is like Facebook and other social media -- a must-have in today’s Internet-driven consumer experience. But it’s a must have that must show sufficient return to justify growing investment in it. A reputable SEO firm can measure that ROI.

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