Can SEO lower my conversion rate?

It can lower your conversion rate since there will be more people coming to your website overall. The % rate may go down, but the total number of conversions will likely rise. That is unless you're practicing black hat SEO that is sending tricking people that have no interest in what you offer into going to your site.

As John points out the total number of conversion will increase if you get more traffic but a big point is that you need to optimise for keywords that actually drive conversion. If you are a car website that only sells used Ford Mustangs and you spend your seo efforts getting ranked for Toyota Prius.

While you will get more traffic because you will start getting visitors for both Ford & Toyota keywords but it won't be relevant so lower conversion rates because you only cater to Ford Mustangs.

SEO is much more cost effective long term so if your conversion is dropping it might be down to the quality of keywords/traffic you are attracting.

Yes, your conversion rate can go down with greater SEO success, and by I define SEO success here as acquisition of more traffic from organic search engine listings. However, as others have already pointed out, the number of conversions should actually go up as long as the words you are attracting traffic for are fairly relevant.

Two reasons I can see for this happening:
a) While you may focus your optimisation effort on a particular phrase, your site could be ranking for and driving traffic for several variants of that phrase (with different prefixes and suffixes), many of which may not be the most appropriate for your site and hence lowers conversion rate.

b) The more 'generic' or broader the terms you attract traffic for, greater is the likelihood of your conversion rate going down, simply because the intent behind the search can vary that much more.

Anything can lower your conversion rate. Design, layout, short copy, long copy, video, etc. Without knowing whether you are speaking about a lead gen, opt-in, or ecommerce type of site it's difficult to give you the most useful answer. If it's ecommerce, i'll defer to the ecommerce brains in the Focus community. If it's lead gen however, I would say whatever you might lose in conversion rate from making SEO concessions and adjustments, should be more than made up for in disciplined testing of boldly different calls to action in a space above the fold on each and every page where it makes contextual sense.

For example if you let's say saw a 20% drop off in conversion rate due to longer copy, or slightly massaged keyword driven headlines, you should be able to more than see a 20% gain in conversion rate by changing the wording in your call to action, the visual color of the call to action, or even including it at all (sometimes it's amazing how often webmasters don't even have the conversion point clear and above the fold).

I debated with one client recently on the importance of simply making the call to action obvious at the top of each page (aesthetically unpleasing to the client's taste). They trusted me and saw and immediate increase in conversions from the same traffic by 140%.

I have a helpful guide to this kind of stuff on my home page at www.miechiels.com

you might also find this article helpful:
http://searchengineland.com/it%E2%80%99s-not-all-about-conversions-taking-a-w...

The principles of Search Engine Optimization (SEO) and Conversion Rate Optimization (CRO) are complementary and they should help each other if done properly.

However, solely focusing on SEO often does hurt conversion rates. This is usually the case with brute force SEO practitioners who use keyword stuffing and technical-oriented SEO tactics. Their websites tend to be nearly impossible for humans to use.

Conversion optimization can help your SEO efforts in several ways:
- A page that’s optimized for conversions will be more usable and visitor-friendly, which makes it more likely to receive inbound links and referrals
- Search engines will index pages more highly that are updated frequently, so it doesn’t hurt to keep the layout and content fresh
- A conversion optimized page should be using more relevant keywords that match what visitors are searching for

You may find this article helpful on How to Do Conversion Optimization and SEO Together: http://www.widerfunnel.com/conversion-rate-optimization/how-to-combine-conver...

By selecting a good business model, and SEO, a seemingly sizable cost will often multiply itself into a considerable profit in just a few years. Don't look at the costs involved; look at the return your investment will bring.

I think Johnathan summed it up nicely. So ..
- SEO can lower my conversion rate (since there will be more people coming to my website )
- SEO can increase my conversion numbers (since there will be more people coming to my website ).
You also need to define what is a conversion. For example, we use technology that captures the business addresses of visitors that come to our website from our SEO efforts.We can take action on these business visitors, so in this case SEO almost always increases our conversion rate too.

This is an old question, but I thought I would post something to consider. Websites can be OVER-optimized for SEO, to the point that body text is so saturated with keywords and keyword phrases that it becomes silly to read. Likewise for heading level tags. As a result, visitors bounce.

If your text does not appear to be natural, people will stop reading it and leave your site. Also, Google is now coming down hard on over-optimized sites.

It can lower your actual conversion rate because of a little discussed phenomenon. As Internet users have become more savvy, many will often skip the first 2 to 5 pages of listings because they are aware that many companies use questionable SEO practices to obtain high rankings or a single company or two may have many listings on the first page.

First page ranking is no longer the be all and end all of marketing and conversion. As search engines continue to refine their parameters for ranking what works for rankings can change. Using flash is no longer a great thing as it slows page loading and speed is now a factor in ranking. It is important to stay abreast of changes in how your site is searched and ranked by search engines and what changes are made in the definitions of black hat practices.