This is a question we get a lot: How much does SEO (Search engine optimization) cost? It's a simple question with a complex answer that I'll try to explain as concisely as possible. First, I'm going to define exactly what I mean by SEO, because it's often misrepresented and overly simplified as something that can be done once and then ticked off a checklist.
When you design and develop a website, there are many on-page and technical opportunities for optimization, but that's not where it ends. Optimizing a website is an ongoing campaign than encompasses a far greater number of ranking factors.
What is Search Engine Optimization (SEO)
The short definition of SEO is, as defined by Moz, "the practice of increasing the quantity and quality of traffic to your website through organic search engine results".
Except that's just what SEO is – not how it's done. That's something we need to explain in order to quantify a cost associated with SEO.
Let's think of Google Search (sorry, Bing & Yahoo) not as a "Search Engine" but as an "Answer Engine". People come to Search with questions for which they need answers. If Google were to disappoint them by giving the wrong answers, people would stop using Google, which would cause Google to lose money.
"But Google doesn't make any money when I use the search function!"
Actually, they do. Your attention is a valuable thing, and almost every time you perform a search, you're served an ad. They look like this:
Which brings up another point: there's literally no reason for Google to openly tell businesses how to rank highly in Search. Doing so would negatively impact the demand for paid search ads.
That makes figuring out how to rank highly in Google Search extremely challenging. The deck is stacked against you. Think about it, not only are you competing with your direct competition, you're also competing with Google itself.
So, how do we determine how Google decides to rank pages? Testing. Lots and lots of testing. Lucky for you, SEO-ers (that is, search engine optimizers) have done that initial research. Here's how search engines determine how to rank websites.
Page Level Keyword & Content Features
This is probably the most obvious of all ranking factors, and most commonly what's done during the initial web design project. Simply put, this is how often a keyword or keyphrase appears in the body content of your webpage (note: more is NOT necessarily better). There's some basic things like meta titles, meta descriptions, and alt tags that can all improve on-page SEO.
There's other things to consider, like how often and how densely the keywords appear and whether or not they're relevant to the topic you're discussing on the page. Essentially, you can't trick Google into thinking you're talking about one, really popular thing, but actually selling something much less popular. Extreme example: stuffing the phrase "Taylor Swift's new album" into a page where you're selling beet juice to increase traffic.
Page Level Keyword-Agnostic Features
This is everything else in the copy of your website that aren't keywords, like length, readability, and load times. This is often overlooked, but quite important. Google considers several factors to determine how much people "like" your site, meaning how relevant it is answering their questions. They do this by measuring things like bounce rates (how frequently visitors leave your site after visiting just one page), amount of time spent at a page, and other factors.
Domain Level Keyword Usage
Let's pretend you wanted to find, say, a paper company in Scranton, PA. A company who's domain has some of the keywords (PaperFromScranton.com), or all of them Papercompanyinscrantonpa.com), will have a slight edge in ranking. Moz says that this is roughly weighted by Google at 7%, so don't go spending thousands to get a domain with an exact phrase match and expect all that much in return.
(Dunder Mifflin will still likely get the business anyway, thanks to Dwight Schrute.)
Domain Level, Keyword Agnostic Features
Things like Domain name length, SSL Certificate, Top Level Domain extension (.com, .org, .net etc) all have a little something to do with SEO. A few years ago I would have been reluctant to even include this in any list having to do with SEO, but with the addition of hundreds of additional Top Level Domain extensions, this has become a little more important.
It's also smart to have a memorable domain name that's sensible. Don't include terms like LLC, Incorporated, or Corp unless that's part of your recognizable brand name (City Corp would sensibly be named CityCorp.com, but DunderMifflin Incorporated shouldn't be DunderMifflinInc.com)
User, Usage, & Traffic/Query Data
How many people find, interact, and use your website all factor into how well it's going to rank. If this feels a little like "Chicken or the Egg", that's because it is. But it's an important one. If someone searches for a keyword you've ranked for and passes over your site, your Click-Through Rate (CTR) goes down, signaling to Google that your site isn't a good option to continue showing (aka, not a good answer to the question). The inverse is true for a site that initially might rank lower, but experiences an increased CTR - signaling that it's a good source, thus causing Google to rank it higher so searchers find it more quickly.
Domain Level Brand Features
These are a little vague, but essentially, they consist of offline usage of your brand name, as well as mentions of the brand in the news and media.
Domain Level and Page Level Backlinks
Backlinks are links on another domain that point to your domain. This is considered one of the most important ranking factors because it tells Google how many other websites consider your site a valuable source of information. Every website has a Domain Authority between 1-100, and backlinks are a major factor in determining this. But it's not just quantity of backlinks that's important – quality of backlinks (links from pages with a high Domain Authority) is of vital importance. It's also important to make sure that no spammy backlinks are hurting your authority.
The quality and quantity of your domain's links being shared via social media factor into ranking your page, because it shows Google that it's a popular source of information.
Adding it All Up
So, how much does all of this cost to identify and implement? Well, that's still difficult to pinpoint, because every website has a unique set of hurdles to overcome.
However, you came to this post for an answer to the question, "how much does SEO cost?", so here are some very broad, general guidelines:
For those of you with focused budgets, one time on-page SEO should be the bare minimum any organization. Initial keyword research, competitive analysis, and long-tail keyword identification will aid in crafting body copy, meta titles, meta descriptions, headlines, and alt tags for your images.
At this level, we're talking about implementation of the basics, as well as on-going research, competitive analysis, SERP (Search Engine Ranking Position) monitoring and improvement, & backlink monitoring and generation.
Ongoing content creation is perhaps the most effective strategy as it encompasses all ranking factors and consistently gives you the best chance to rank highly.