4 Common UTM Tagging Mistakes Made by Online Retailers (and How to Fix Them)

Posted by Rita Braga Martins 7 Aug 15

shutterstock_295939298This post follows on from our ‘Definitive Guide to UTM Tagging in Ecommerce’ guide and infographic, which you can find here.

UTM tagged links are there to make it easier for you to analyse marketing performance and channels, to ultimately gain a better understanding of your visitor and customer buying behaviour.

But what if you’re already tracking your campaigns and still find it hard to draw conclusions from the results? What if the data you’re collecting does not make sense, or match up to what you were expecting? What if you can’t find a specific campaign? Or what if you’re tagging your links incorrectly, but are not aware of it?

We have listed some common mistakes we often find in UTM tagging by retailers, and how you can make sure to avoid and correct them:

1) Your email software doubling-up tags in your tracking links

Some of the most popular email solutions generate their own UTM parameters by default, such as utm_medium=email, and add it to the end of your email links, which can affect your tagging. Considering that the last parameter will override the first in the case of duplicates as a rule-of-thumb, any visits to a doubled-up link will be tracked by the email provider’s tags.

This is what a doubled-up UTM tagged link looks like:


As you can see, all three tags were doubled up and attributed a different name. If you were to search for your campaign ‘lipstickjuly15’ in your analytics software, you might find that your traffic has not been classified as you expected - since the last tag is the one that counts, it would mean that visits to this link would be attributed to utm_campaign=fc174Monday+January+2015 rather than utm_campaign=lipstickjuly15, for example.

What you can do:

  • Make sure you’re informed about all the specific settings in your email software, and create your UTM tagged links accordingly.

  • Be particularly wary of this if you’re doing any joint marketing with another brand or provider - even though your email software might not append its own UTM codes, it could be the case that your partner’s does.

2) Using Source and Medium tags in the wrong way

We understand that the Source and Medium parameters can easily be confused - which is why retailers often misuse (or fail to take advantage of) them when creating their tagged URLs.  

There are three common situations where the Source tag is used incorrectly, and although these mightn’t be considered errors, it is important that you tag your marketing activities consistently in a relevant, meaningful way that best allows you to assess channel, source and campaign performance.

Here are the three common situations:

a. Confusing the purpose of Medium and Source parameters

Some retailers use UTM tags to distinguish between different types of traffic within a particular channel, such as Twitter. For example:

  • utm_source=twitter+ad for a Twitter ad they promote.

  • utm_source=twitter+post for a Twitter post they publish.

However, this is not the way these tags are supposed to be used, and it will cause your reporting to be misleading or simply not useful. The medium and the source tags are meant to provide different types of useful information.

How you should use them:

  • Follow the standard Google model and use Source to identify the channel, and Medium to identify the type of marketing in place, as follows:

    • utm_source=twitter (for both the ad and the post)

    • utm_medium=cpc (for the twitter ad) and utm_medium=social (for the twitter post) - this will let you compare the paid vs unpaid marketing traffic from Twitter

Another situation is when retailers swap what they tag as Medium with what they should be tagging as Source. Here is an example:


What you should do:

  • Remember that the Source is the name of the referrer, and is meant to tell you which specific channel generated the visit - so you can look at, for example, Facebook and Instagram separately when measuring the performance of each of these Sources under your social media (which is the Medium) activity. The type of marketing should then be identified in the Medium tag - email, social media, CPC, etc. So the above link should be tagged as follows:


  • In the case of email marketing, avoid using the name of your email software as Source (eg. utm_source=mailchimp) and instead use something that will allow you to measure, for example, your welcome triggered campaign vs your regular newsletter (so use utm_source=signup and utm_source=newsletter).

b. Duplicating Medium and Source in the same URL

We sometimes find retailers using links with the same Source and Medium, for example:


What you should do:

  • If you’re going to use email as a medium, don’t also use it as a source and instead specify the type of email - as we've mentioned before,make sure you’re obtaining as much different and relevant information as possible from the visit through these tags.

3) Incorrectly using ‘&’, ‘=’, ‘?’ and ‘#’ symbols in UTM parameters

This is one of the most common mistakes undermining an accurate campaign analysis - the incorrect use of specific characters when creating your UTM tagged links.

a. The ampersand ‘&’

Because no spaces should be used in URLs or UTM tags, other characters must be used to separate two or more words. However, the ampersand already has a specific meaning when it comes to tracking links - it is the character that separates UTM parameters, so it should not be used for anything else in that link.

This is the incorrect version that we often see:


(Note that if you were to analyse this campaign, you would find that it would be listed as utm_campaign=red only, as the word after the ampersand would be disregarded as being part of the tag)

This is how it should be:

utm_campaign=red+lipstick or utm_campaign=red_lipstick or utm_campaign=red-lipstick

What you should do:

  • Use ‘+’, ‘-’ or ‘_’ if you want to separate two or more words, to ensure an accurate tracking and analysis of your marketing activities. Caveat: note that sometimes the ‘+’ may be converted to a space, in some analytics software.

  • As an alternative, you can also use ‘%26’ to separate words in any UTM tag (so utm_campaign=red%26lipstick).

b. The question mark ‘?’

Only the first UTM tag needs a question mark placed before it - other tags should be preceded by an ampersand. So if ‘?’ is already present in the URL, you don’t need to add it again before the UTM parameters. Here are examples of both situations:

i. If there isn’t a question mark in the URL: http://www.beautystore.com/red-lipstick

This is how the campaign link with UTM tags should look like:


ii. If there is a question mark in the URL: http://www.beautystore.com/product?id=red-lipstick

This is how the campaign link with UTM tags should look like:


c. The hash ‘#’ and the double hyphen ‘=’

These two symbols ‘#’ and ‘=’ also cannot be used inside a UTM tag value.

Golden rules:

  1. Make sure your final URL only contains exactly one question mark ‘?’.

  2. Each parameter must be preceded by an ampersand ‘&’, and this is the only way you can use the ‘&’ in a tagged link.

  3. Never use ‘&’, ‘#’, ‘=’ or ‘?’ inside a UTM tag value.

4) Mixing lowercase and uppercase in the same tag

UTM tags are case sensitive in Google Analytics, so for example ‘Cpc’ and ‘CPC’ will be recorded differently. Forgetting about this rule can make your analysis of a channel or a campaign rather inconsistent over time.

What you should do:

  • Decide on a clear structure for naming campaign names, sources, etc., and then stick to it every time you create a new tagged link. We would recommend you use lowercase for Source and Medium as that’s how auto-tagging tools like Adwords or Bing currently do it.

We hope this post raised your awareness to some common issues made when tagging your links, and how to avoid them to ensure that your reporting is consistent over time and that you're extracting as much value as possible from each tag.

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Topics: Ecommerce email marketing

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