10 min

URL shortening services allow you to quickly and easily turn a potentially long link into a really small one. This is great in a variety of scenarios, from social media posts to email messages. They’ve become extremely popular, and are used extensively by a number of Web applications (at MailUp, we have our own URL shortening system that is used automatically when you post messages to social networks from your MailUp account).

Although they can be a great way to include short & cute links in your email messages, URL shortening services should be used with caution because – unfortunately – the bad guys use them too! They are used by malicious users to hide harmful links behind a familiar look, such as that of a bit.ly URL. As they get misused, these services can end up on the “red flag for spam” list, and negatively affect your own messages, if you include them.

Bit.ly blacklisted by Spamhaus

For example, recently Spamhaus again added popular url shortening system bit.ly to its domain black list or “DBL”. Su.pr – the URL shortening service used by Stumble Upon – is also listed (see table below). Since many spam filters use Spamhaus and other blacklists in their “is this spam?” algorithm, the inclusion of bit.ly- and su.pr-shortened URLs can negatively impact the deliverability of messages that include such links.

Here are some of the most popular URL shortening services and their status in the Spamhaus domain blacklist

URL Shortening Service Spamhaus domain blacklist (10/10/2012)
Bit.ly Listed
Deck.ly Not listed
Goo.gl Not listed
Ow.ly Not listed
Su.pr Listed

So, should you avoid URL shortening services completely? As the table above shows, even among the most popular ones, there are some that – at least as of today – are not blacklisted by a system like Spamhaus.

What should you do? The rule is: “proceed with caution“. In MailUp, this means – for example – that you should always use the email Check-up feature before you send a message to your subscribers to find out if there are any issues. The Spam Check tab of the Check-up page will show links to domains that have been blacklisted, as shown in the screen shot below.

Spam check feature

All in all, email marketers can definitely take advantage of URL shorteners, but should do so with caution as the deliverability of their messages could be negatively affected if the blacklisted URL shortening services are used.

Liked this article? We have plenty more in store for you.

Subscribe to get news, tips and updates delivered to your inbox.

Read also

What Can the Best Email Marketing Campaigns Teach Us?

We've looked into four established brands and their email campaigns - and we've found out a few interesting facts that make their newsletter strategy extremely ...

Read more

9 Can’t-Miss Tips For Your Halloween Email

Halloween-themed emails have been trickling into our inbox all month as brands seize the opportunity to deliver sweet treats and ghostly content to subscribers. But don’t be spooked if you ...

Read more

How to Write Effective Email Subject Lines

Email marketing successfully stands the test of time for over two decades. As a matter of fact, it seems like email marketing is stronger than ...

Read more

What Differs Good Emails from Mind-Blowing: 7 Factors

Subject, focus, follow-up and much more. Here are 7 operational tactics to create brilliant, effective and customer-oriented email campaigns. Every time something new comes along in ...

Read more

3 Email Marketing Tactics to Encourage Impulse Buying

Email marketing is one of the best channels to drive traffic to your website. Not only can you use it to share news about your ...

Read more

Tutorial: How to Create a Color Blocking Email

We are very fond of all things color in email. One style we totally love (and see a lot) is color blocking, where about half ...

Read more