About a month ago, I decided to test twitter ads and I set up a campaign for my newsletter.
This was a "lead generation" campaign, that gives users the option to subscribe to a service by just clicking a button —and twitter automatically submits their username, name and email to the underlying service— and I took advantage of MailChimp's form integrations.
I gave the campaign a $10 total budget and a $2 daily budget, targeted my twitter followers, and let it run for 5 days.
I got 27 leads, which means it costed me about $0.37/lead. I actually ended up with 22 new subscribers originating from the twitter campaign (probably some of the leads were already my subscribers, or did not complete the signup by clicking in the opt-in validation email sent by MailChimp), so the actual cost/signup was $0.45.
By having a look at the leads graph, it looks like the first and the last days of the campaign were much worse than the main body of the campaign, which leads me to believe that if this was a real campaign, that lasted more days and had a better budget, the average cost per signup would have been around $0.30.
On one hand, this was a very targeted campaign ("If you follow me on twitter, you'll probably like The Letter"), but on the other hand the budget, design and implementation was not professionally done, so it's hard to draw conclusions on the cost per lead of a "real" campaign.
In any case, I find this kind of Twitter ads extremely interesting, mainly because a user can give you their contact details without filling a form —just by clicking on a button.
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