Why iFrames are a bad idea for redirecting your site

For the average SEO expert its a head-slapping discovery: a site owner has two domains (say a .com and a .co.uk), wanted to show the same site on both domains, and therefore put an iFrame on the .com site that contains the contents of the .co.uk site.

Briefly, these are the reasons why this is a really bad idea:

• The URL never changes – when users go to the .com site they see “domainname.com” in the browser, and the contents of “domainname.co.uk” in the iFrame. If they click on any links, the browser URL stays as “domainname.com”. If the user bookmarks the page, or wants to send a link to a friend, they end up sending just “domainname.com”, and when they return to the site they’re right back at the beginning again.
• Secure encryption doesn’t work – when the user gets to a secure page to checkout page, the security is all messed up because they’re still accessing the page within an insecure iFrame, so they’ll get all sorts of warning about incorrect certificates. This causes trust issues and could stop the user buying, or even returning to your site ever again.
• Wasted links – because the same site is on two domains, if someone links to “domainname.com”, then “domainname.com” gets all of the credit for that link, and it doesn’t help the natural search rankings of “domainname.co.uk”. You’re optimising for two sites instead of one, and therefore need double the effort.

Instead of using an iFrame to do this, use a 301 redirect to point the .com domain to the .co.uk domain. Its a little more complex, but once its in place its completely search engine friendly and completely user friendly. You can also do it retrospectively – so if you’ve been using an iFrame for years, doing the 301 redirect now will do no harm. In fact it will probably make your .co.uk site rank better.

For information on how to create a 301 redirect, see this tutorial. I’ve also put together a post describing how 301 redirects work.