Data Quality

Data hygiene: clean data boosts marketing ROI

With a median ROI of 122%, email is more effective for marketing to consumers than social media and paid search.1 That ROI, however, is dependent in part on the quality of your customer data base.

When Bad Data Happens to Good People

There are many reasons a database may contain bad data. Customers may have opted out of communications or contacts have moved addresses. You may be missing simple but vital pieces of information such as last name, address, or email. You can have duplicate records. While there are many more variables in the “dirty data” scenario, they all can diminish ROI through inefficiency and extra costs.

At the most basic level, bad customer data leads to deliverability issues. It’s hard to generate revenue from an email that doesn’t make it to the intended inbox. Dirty data can also lead to Spamhaus blacklisting or major ISP blocking, which have their own economic implications.

With cross-channel communication, the stakes are higher. If you can’t trust the quality of your data, every insight and campaign strategy you develop based on it can (and probably should!) be questioned.

Get Started with Data Hygiene

Every digital marketer should appreciate that data is what drives revenue. Yes, eye-popping creative, amazing offers, and free shipping are all wonderful. But data is your biggest asset.

Let’s be honest, maintaining customer data may not be one of the most glamorous aspects of marketing. However, your company has invested a lot of time, money and resources into building a database infrastructure that drives results.

Cleaning a database isn’t a “one and done” type of job. After all, your database is constantly changing, so having clean data that increases ROI is a process and this process should be one of your top priorities.

Good data hygiene has two steps. First you should “identify incomplete, incorrect, inaccurate or irrelevant parts of the data” (Don’t you love all the words starting in “i” from this Wikipedia definition?) Next, you would complete, correct, delete, or modify the dirty data.

Data Hygiene Best Practices

To get you started with data hygiene, we suggest these three basic areas to address. Over time these simple steps will result in a cleaner database that requires less upkeep. You’ll see substantial cost savings as well as better response rates and higher revenue. 2

New subscribers: Developing good habits when it comes to data hygiene starts with the information you collect from new subscribers. Real-time validation of an email address at in the point of entry ensures the information you collect is accurate even before it enters your database. Confirming the correct email is especially important if you have store associates asking customers for their email.

Reduce bounce rates by confirming an email address is correct. Ask subscribers to enter their email twice; use entity forms like “captcha” and “recaptcha” to make sure real people are entering info; or employ a double opt-in process to confirm they want to hear from you and ensure that their email address is correct. Pay special attention to email addresses captured at point of sale and follow-up with a confirmation email. Verifying data increases the chance of converting the subscriber to a paying customer.

These additional tips can help increase the validity of customer data entering your system.

  • Collect data in small “bites” – Keep data entry simple. Don’t ask people to give up too much information at one time. Maintain goodwill by asking for less. You can use other communication points as you build the relationship to request additional information. Make sure to offer something of value in exchange for the information you receive.
  • Collect data in a standard format – Think carefully about the information you want to capture. This means considering who else will be collecting and using the same information – such as customer service. Looking at where your needs overlap will help you create a form that captures the same data in the same format.
  • Improve data accuracy – Add tools to forms that validate information as its being entered. An example is a phone number that requires 10 digits to be valid. One of the best ways to make it easy for visitors and limit input errors is to employ checkboxes and drop-downs that already contain the information you want in the way you need it. This practice can make a huge difference when you consider that 20+ percent of email registrations contain typos, syntax, domain, and other errors.

Inactive subscribers: One major way to improve the ROI of your campaigns is to make sure you’re only reaching out to customers who want to hear from you (i.e. are engaged). Why waste time sending an email that will be deleted or remain unopened?

Before you write this group off entirely though, keep in mind they’ve shown interest in your brand in the past. Many of these inactive members are more likely to convert than a newly acquired subscriber, especially if they’ve purchased. And as marketers know, re-engaging an existing subscriber is always more cost-effective than acquiring a new one.

So, take a closer look at your database and find an opportunity to reach out to customers who are still mailable but no longer engaged. Developing an effective reactivation strategy is a great way to open a dialogue with customers.

Existing List of Subscribers: Your current mailing list is the life blood of your marketing programs and maintaining its quality is key. You should remove bad or poor quality addresses on a regular basis or before a major campaign to optimize your mailings.

  • Duplicate addresses: The easiest step to database maintenance is removing duplicates. Take this opportunity to compare the information of two or more entries with the same identifier (say, email address) and merge the two records to form the most accurate listing.
  • Invalid addresses: You’ll want to minimize bounce rates by removing misspelled or improperly formatted addresses. Many of these bounces are the result of simple typos and can be easily fixed. Take the case of “” where you can put the “@” where it belongs. You can then validate the corrected address and avoid losing a potential customer. In the case of hard bounces, we suggest three to five occurrences before removing the email from your customer data base.
  • Role addresses: You don’t need to mail to an address not associated with an actual person. So purge addresses that start with “sales@” or “info@” which generally end up in “catch-all” inboxes.

Clean Data Pays Off: the Proof Is in the Pudding

Efforts to ensure the integrity of your data can greatly enhance response rates and increase ROI. To help you demonstrate the improved performance of a cleaner customer email list, you’ll want to track the “before/after” of several key metrics including:

  • Inboxing rates
  • Hard bounce rates
  • Open rates
  • Click-through rates
  • Unsubscribe rates

So keep your eye on the prize: greater engagement and higher revenue. Be sure to conduct regular data hygiene since it’s one aspect of increased ROI that marketers can easily tackle.



Anshul Sharma
Sr. Analyst, Intelligence Products

Anshul Sharma is an Intelligence Products Analyst at Data Axle. His background lies in Economics as well as Marketing Analytics. Along with his love for sports (namely basketball, football, baseball, and of course hockey), Anshul is also a huge movie buff.