The principle of one link

Web services send notification emails. The links in such emails serve a sole purpose of bringing users back to the services’ websites. Therefore, there should always be exactly one link per such email. The flow: the receiver clicks the blue underlined text without even reading anything and ends up in the right place.

Example: an email to confirm registration by following a special link

Typical mistake (the links in the example don’t work, obviously):

Dear Ilya,

You have tried to sign up for the Exciting Service. To confirm your registration please follow the link. Make sure to subscribe to our blog to get the latest news and go try our great iPhone app!

Sincerely,
Exciting Service’s team

To take an action, I need to read and understand all the crap that the author has written here.

Here is the right way:

Ilya, confirm your registration:
Confirm and start using Exciting Service

Exciting Service

The right place to tell the user about the blog and the iPhone app is the website itself. You will have more room to talk about them, and the user will be much more motivated to check them out after he or she has completed the registration.

Example: an email to notify you about a shipped online order

Typical mistake:

Greeting from AwesomeBooks, dear customer Ilya!

You have ordered the book “How to Order Books Online” by James Writer (see your order history). The books has been shipped, and the tracking code is WTF4382430324.

Learn more about shipping and delivery, warranty and return policy. If you have any further questions, contact the support.

There are 0 items in your cart. Since you have bought the book “How to Order Books Online”, you might also be interested in “Underlining links: an essential design skill”, “What makes an email notification bad” and “What should one do if he cannot come up with a third stupid book name”.

Thank you very much!

Your AwesomeBooks

Notice how the only thing that interests me, the tracking code, is not a link.

Here is the right way:

Ilya, the book “How to Order Books Online” has shipped to you.
Track the delivery and see more recommendations

AwesomeBooks

The links leads to a page with tracking information, recommendations and all the service links.

It may seem hard to leave just one link in an email. What if you need both this and that? The solution is to change the approach: treat the whole email as a link. There is only one by definition. Ask yourself: “Where does this email lead?”, and it will all make sense.

Obviously, the principle is not applicable to email designed for reading and thus does not lead anywhere.

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