Edit: Google has introduced a new GSP interface that prevents this hack from working. You’ll still be able to use the old interface for a few months, but after that? RIP GSP hack.

If you are a Gmail user, you are no doubt aware that last year Google released tabbed Gmail. It was mostly received positively as it gives us a great way to keep our inbox organized without actually having to do any work (thanks Google). We are also now one step closer to tabbed everything.

For those not aware of the changes, see the screenshot below of the new and improved Gmail.


Promotions in Gmail

As a digital marketer, I find one of these tabs especially important: the promotions tab. The promotions tab is where Google automatically files away any brand marketing emails – those pesky, persistent subscriptions we all inevitably receive, but probably don’t remember signing up for in the first place. Regardless, Google included a little something extra in the promotions tab: Advertisements….disguised as emails!


These ads are appropriately known as Gmail Sponsored Promotions, and they have very quickly become a popular route for cheap, highly targeted traffic for advertisers.

For marketers, GSP rocks. We have the ability to target users based on the content within the email that they receive (welcome to 2014). This means: keywords, domains, interests, recent purchases, and job title.

One thing that doesn’t rock about GSPs? Misleading CPCs.


Sometimes a click is not a click

When you set up a GSP campaign, one of the first things Google will have you set is a Max. CPC.


It’s not out of the ordinary to assume what you are placing a bid on here is a click to your website. Unfortunately, many of us learned the hard way that this is not the case. What you are actually bidding on here is a click to open the expanded ad. This has led to a lot of puzzled advertisers paying 3-4 times as much as their CPC bid to get a click to their website. Why? In the world of GSPs, a “click” is not truly a click.

What we consider a click in GSP is called an “External click”. But… we don’t have an option to set an external click bid. Until now!


How to get website clicks for lower CPCs

While we don’t have the ability to bid to external CPC, GSP does offer a conversion optimizer tool just as Google gives us in AdWords. One thing I noticed within the last two months is that Google added external CPC as a conversion within this tool. If you want to bid to an external CPC, simply turn this tool on, set external click as your conversion, and then set your max external CPC bid as the goal. (Set the other “CPC” target to be one-third of the External CPC bid.)


Does this actually work? Yes!

We are running GSPs for one of my clients in the online video vertical, and we wanted to take advantage of GSP targeting options and low marketer saturation to get as many clicks to their website as possible at the lowest cost (groundbreaking strategy, right?).

Before we discovered this CPC trick, we were trying to get low-cost clicks by setting the teaser CPC bid as low as possible. $0.05 is as low as Google will allow, so we set bids to $0.05 and let them run. Right away we were seeing pretty horrible external CPCs, as high as $1.00 and no lower than $0.60. This is before we discovered the external CPC hack. We decided to test it with what we would consider to be a very low CPC in paid search, at $0.15.

Here are the results:


Game. Changed.

We hardly took a hit in overall traffic, because it was coming in so much cheaper and these clicks also happened to be more engaged. Likely because you are required to use the GSP “Targeting Optimizer” tool before you can turn on Conversion Optimizer.

Worry not, targeting optimizer has also proven to work as part of this whole formula. With this enabled, Cost Per External Click dropped from $0.72 to $0.19.


The client has been very pleased with GSP performance, and we continue to invest in the channel and are seeing awesome results. I would recommend them for almost any client!

This is the first post in my series of guides on GSPs. Look out for my next post about using GSP for lead capture.


  1. Brooke Sault March 12th, 2015

    great post!

  2. Dan Perach June 3rd, 2015

    Is this from the old interface? I don’t see this option.

  3. Sean McEntee June 3rd, 2015

    Hey Dan,

    Yes this is from the old GSP interface. This tactic would still be possible if you create a conversion event for a visit to your landing page and optimize to that.

Leave a Comment

Sean McEntee
Sean joined 3Q Digital in November 2013 after working previously at Performics and iProspect. Sean holds degrees in Interactive Media from DePaul University and Business Administration from Linkoping University. When he's not helping innovative companies grow, Sean enjoys traveling, building computers, and fondly recalling that one time the Golden State Warriors blew a 3-1 lead to the Cleveland Cavaliers.