Case Example: How we increased sales by 139.16% with testimonials while reducing advertising budget by 21.81%

Trustmary teamTrustmary team
Last edited: December 12th, 2023

Case Example: How we increased sales by 139.16% with testimonials while reducing advertising budget by 21.81%

From time to time, we are asked how much difference can be made by using testimonials effectively. There is nothing universal about this that would apply in all situations. But we know that in some situations, the differences are huge.

To prove this, we conducted an experiment with Wellness Tools Group, whose main product is Mutjutin. Mutjutin is a massage tool with over 30,000 users, with customer satisfaction of 8.88 on a scale of 1-10. So this is a product that its users really like. Mutjutin had previously implemented Trustmary’s testimonial tool and had received a lot of positive feedback from customers, but those testimonials had not yet been effectively implemented.

That is why we decided to try what happens if we help by implementing the testimonials as well as we could.

Challenging starting point

The starting point can be considered challenging in many ways. The advertising ROI had gone negative, and a clear change of direction was needed to regain advertising on a solid footing. The test was conducted between the 4th of June and 11th of August 2019, and the reference period was March 27-June 3. The implementation period and the reference period are thus of equal length.

As far as data is concerned, there is only fully comparable data on purchase volumes, not actual purchase value. Although average purchase value has remained stable over the period, clear conclusions can be drawn from the volume of purchases. However, tracking of purchase values ​​on the main ad channel on Facebook only started after the test was launched, with conversion tracking initially lacking.

139.16% more sales, 21.81% lower advertising budget

The test was done completely on the Facebook Instagram axis and here are the results.

Number of sales: before 286 -> after 684; an increase of 139.16%
Price per purchase: before 21.69€ -> after 7.09€ ; dropped 67.31%
Media Budget: Before 6203.28€ -> After 4850.06€ ; dropped 21.81%

How did we implement the references?

References were already in use on the product pages but had not yet been used in the Facebook or Instagram ads themselves. To start off, we tweaked the product pages a little to make references more visible and make buying easier. And then we made the biggest change that made all the difference; we wrote ads that were basically just full of customer testimonials.

Unfortunately the ads are in Finnish so you cant really evaluate them yourself, but you can see the top performing ads texts below.

In conclusion

When used properly, testimonials can get pretty great results. However, it is good to remember that getting testimonials per se will not save you if they are not effectively utilized.

In this case, the testimonial tool was already in use and embedded in the website, but the utilization of the testimonials in the advertising itself had just been forgotten. As the example shows, sales were more than doubled with testimonials, even though the advertising budget was reduced at the same time.

Trustmary team
Trustmary team


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