How fast your website traffic increases from SEO depends on many different variables. Of course the first and most important variable is how much SEO are you, or the agency you hired, doing? A few hours a week will most likely get a different response than 100 hours a week. For the sake of discussion let?s assume you hired a great agency, like ours, to do your SEO and your budget allows for 10 hours a week.
The next variables are really site-dependent. How old is the site and how many unique pages are on the site and indexed by the search engines. The more quality pages that are indexed and the older the site, the faster we can likely make the site move up in the rankings. New websites in competitive market spaces will often have to be patient to go after the whale rankings they desire. A better strategy for a new site is to aggressively go after the long tail searches that may have a much lower exact search match, but create very high conversion rates and are attainable in the first twelve months.
More variables that affect ranking performance are the quality and age of links that point to the site currently. Most amateurs do not have the time or skill to build a sustainable linking campaign that will drive rankings upward. A good quality linking campaign helps new and old sites. A few great old links can be worth their weight in gold. New links from social media campaigns are now almost a must have to achieve and sustain top positions for tough key phrases.
Well, I have given a handful of variables that affect how fast SEO can increase traffic. Here are some answers based on working with thousands of clients over several years. If your site is older and has quite a few pages, site traffic will begin to increase almost immediately from quality SEO work. If your site is only a year old and has only a few pages it is likely it will take six months or so to start to see good results. We have clients that have increased their traffic by 100% per day in the first month after we finish the on-page optimization. The more normal trend though is a 5-10% increase per month starting in month three or four. This average, of course, changes a great deal depending on the market space. If your website is designed to attract people who want to build airplanes at home then you likely have a limited audience compared to a website that is designed to sell shoes. The former will be easier to get all the traffic, but the traffic is likely only a few thousand. A good shoe site could get 500,000 visitors a month.
SEO grows traffic. It is not instant like Pay Per Click, but your investment in quality work will pay for itself 10 fold or more per month in time.