The Dirty Secret of Personalized Email Marketing


August 25th, 2016 marketing processes  



The debate on mass email marketing never stops. And every now and then, someone pulls off a nice story about personalized email marketing, or perhaps I should say ‘Extremely Personalized’ email marketing. By extremely personalized I mean an email that is meant only for one individual. We at KiSSFLOW had the same dilemma: which one was more effective? So we decided to run a A/B test on this.

We picked 200 contacts of identical profile (e.g. job title, size of the company, industry, geography). For 100 contacts, we sent mass emails with some simple personalization like addressing them with first name. For the other 100 contacts, we did deep research about them on social media and wrote very personal opening lines to them before asking them for a click.

Here are the results from this A/B test activity.

email screen3

MM = Mass Mailing /// PM = Personalized Mailing.

The extremely personalized email marketing results are stunning. The open rate is 500% better than the mass mailing and the click rate is more than 200%.

But here’s the catch. The above table doesn’t tell the full story. The thing that is hidden is the effort that required to do either of the activities. Look that table below so that you get the full picture.


A really great email marketer might be able to squeak out 20 of these extremely personalized emails a day. So it takes five full working days to send 100 emails. In that same period, his counterpart doing mass email marketing could have sent out 4000 emails and produced 80 clicks. You may ask, Why not send 40,000 or even 4 million emails? There is significant effort in gathering email databases for the target market we are addressing and curating. We use various SaaS software for this task. We also have internal tools that we run by to check for invalid email addresses and other checks. This all involves manual work and the best anyone can do is 800 curated emails in a day with less than a 10% bounce rate.

So the summary is, purely looking at the numbers, targeted Mass Emailing seems to produce better numbers than extremely personalized emails.

How does this stack up with your experience? Please comment.



  • Kresten Bergsoe

    Personalization is not scalable if you do it wrong. The Kissflow story is a good example of just that.

    If you develop deeply personalized emails and stay with a pushy frequency based promotion strategy – yes, then you have added a huge work overhead and get a ROI that will not compete with traditional blast campaigning.

    But if you build your recurring mails like newsletters with highly dynamic reusable elements – then you have the opposite effect: Same or smaller overhead per email and still the 4-5x increase in response. On top of that you benefit from increased attention from your audience as you are not burning them with irrelevant messaging you normally do. Try calculate the difference one month extra subscriber attention impact the ROI of the average retail house list – and you get see a very different picture. Then you can afford a lot of work to get this right.

    Even frequent promotional emails can be built as recurring triggered messages with a massive level of reuse. As the receiver context, products and trigger constantly change – the resulting message is still on a different planet when it comes to relevance compared to generic blast promotions – and that too will show up in the ROI.

    It’s all about how you do it and where….if you do it right – personalization is massively scalable and probably the most profitable move you can do as a marketeer.

    • sai.padmanabhan

      Hello Kresten,

      We appreciate the time you took to read & comment on the post. Thanks for that.

      Do you have data to show that personalization is scalable? If you can share with us some real statistics based on real data from an actual campaign, that will be very helpful.

      We have not an iota of doubt bout the response or engagement levels personalized emails can help us achieve. But, look at the big picture. If there is a way we can achieve the scale of mass mailers and still retain personalization, we would be very happy to take that route.

  • Anupam

    Interesting post Sai! Agreed that with mass mailing you would might get better numbers (of opens, clicks) than personalized mails simply because of the sheer number of mails being blasted out…but on the flip side it might also irritate some recipients who might even feel offended at the lack of personalization…so the risk of alienating prospects who could have become real leads plus the dent on your brand…

    • sai.padmanabhan

      Hi Anupam,

      The entire intent is to get them read the email. Irritation is a form of reaction too if not response. 🙂

      If an email can evoke an emotion, nothing like it!

      As far as a prospect is concerned, in B2B at least, they are looking for solutions to burning problems. If they can connect with the messaging with their problem, they will be interested. If not, they would ignore. But, all this is under the basic assumption that the email is read & understood. Lack of personalization offending someone is far too an unlikely possibility. Don’t you think?

  • Ashish Bhagwat

    This spells out what’s wrong with singular metrics like Open rate and Click rate. Let me draw a parallel for you. If you were in-charge of a call center, would you want your people to go through more calls in a day and “close” them all regardless of how customers felt? Or would you prefer to ensure that they make every single customer happy, even if it’s only 20% of all the calls one would have taken otherwise? For all you know, those four clicks in personalized messages may all convert to be your customers much faster, and much more loyally than any of those 80 clicks form mass mailers. Misleading experiment. It;s never about a singular open or click, but the prospect journey. I rest my case 🙂

    • sai.padmanabhan

      Ashish, Thanks for taking the time to read & respond.

      Your observation is fairly valid. However, I am sure you do understand that this is part of an overall, end to end outbound strategy. However, this stage of sending cold emails is a vital part of it, which can be well within the context of email marketing. We are not covering the further stages of the outbound process in the scope of this experiment. So, we can leave aside the possibilities of how many would convert into actual paying customers aside, for the time being.

      Now, as far as the emailing exercise itself is concerned, personalisation is aimed at capturing the attention of the recipient. But, irrespective of whether it is mass or personalised, the probability of getting a response is equal for both channels. While we agree that the journey matters the most, the single click or open is the first point of engagement that gets established with a cold lead. We cannot discount the impact of these metrics either. How can an experiment in itself be misleading? Maybe the numbers we choose to interpret are but the experiment itself can never be misleading.

  • NiftyImages

    Very interesting thoughts here. Haven’t heard of companies going this in depth for personalized emails(social media background checks!). We live in the world of mass personalization using content blocks, triggers based off of user behavior in our interface, past interactions with our emails or data we have collected on the user. So we think of ourselves as moderately advanced.

    The NiftyImages products allow for personalized images using subscriber data, or personalized countdown timers, which we obviously use as well. The response that we get and that our clients report is much better than a generic “Hello Sai” in the subject line or top of the email. At the same time, it can be done in Mass Mailing with little setup time. Would love to know where you think this falls Sai, MM or PM.


    • sai.padmanabhan

      Interesting idea! Really sweet of you to make that personalised image. Delighted! From the outset, it looks super-personalised although from your explanation, we gather that it can be scaled beautifully without losing the personal touch.

      I particularly see that this could be immensely successful in social media. When I interact with followers as a group, say after a chat, sending a personalised ‘Thank you!’ note using these images would earn a special place in their hearts & minds for us. Would love to explore.

      Once again, thanks! 🙂

  • Venkatesh

    Padmanabhan, I would presume it’s dependant on what is the Kpi that one is targeting. What are the various measurements that you re deriving? Making generic statement or question may not be the right way.

  • Venkatesh

    Hi, I think it should depend on what we are measuring as the click rate is alone seen as a measure here then it may not be valid one

    • sai.padmanabhan

      I am sorry but I am not following your question. My intent is to reach as many people as possible. Metrics are more of an outcome rather than an intended outcome. 🙂