The pitfalls of having dirty address data

Hand pressing button for data validation to ensure addresses are correct

Whether sending through the post or via email, your address database needs to be spotlessly clean.

Addresses, which include both email and postal addresses, have never been more important than today. Many companies, charities and other organisations hold large quantities of data in the form of postal and email addresses. They find that duplications and other errors and inaccuracies reduce the value and efficacy of their address data. For this reason, they prefer to use Spotless Data's unique web-based data quality API for data you can trust to clean and ensure the data validation of said addresses before sending out a large number of letters to their customers or potential customers. Companies in the UK alone wasting an estimated £220 million per year on mail that fails to arrive at the mailbox the person it is addressed to.


Estimates indicate that 89% of marketing departments use email addresses as their primary form of lead generation. You can hire the best copywriters available and have the best-designed emails among all your competitors but unless your list of email addresses is clean your marketing campaign won't go as well as you would like.

Emails are also used by many websites as the point of contact between the company and their online users, whether for signing in to and verifying an account or for communicating important changes to their websites or their terms & conditions. Not only is it a waste of effort to be sending out large numbers of emails to badly formatted email addresses but it can also cause legal complications if the dirty email addresses being used result in people receiving unsolicited emails. And while a customer may enjoy your email, if they receive three copies of the same email they may get annoyed and decide your products & services are not for them. A single customer view, itself based on high-quality data, may also help.

Postal addresses

Unlike email addresses, which are universal, the rules for postal addresses vary from country to country, making their validation even more complicated than that of email addresses. For instance, a simple 1st line of a UK postal address might be 6, Argyle Terrace. A Spanish person who has recently moved to the UK but who had not fully understood how address structures operate in that country might well say they lived at Argyle Terrace, 6, reflecting how postal addresses are structured in Spain. Companies, charities and international organizations which have postal addresses in multiple countries will need to know the address structure rules in all those  countries, rather than relying on having an intelligent postman who can decipher that Argyle Terrace, 6 actually refers to 6, Argyle Terrace, and who can figure out many other corrupted variations besides.

This issue is made even more complicated by postal codes. A simple example is that in the USA the postal code comes after the state whereas in Malaysia it comes before the state. So an American company with a mailshot for countries in South-East Asia might put the postcode in the wrong place, resulting in some of the post not arriving at its intended destination. Many countries only have a postal code for the entire city whereas countries like the US & UK have a unique postal code for small datasets of addresses, typically between 10 and 20, and so greater care is required.

Costs of having dirty addresses

Given the sheer cost of sending mail through the post having clean postal addresses which have data integrity can save your organisation a huge amount of money. Imagine a charity sending out a begging letter to people who they know have expressed an interest in their charitable work, and which has a budget of $100,000 for sending their mailshot through the postal system. Yet 15% of their postal addresses are corrupted. This means not merely a loss of $15,000 due to the dirty data within these addresses resulting in these letters never reaching their destination but also, if the overall return on the $100,000 investment, assuming all the postal addresses were correct, was $2million worth of donations, then the actual loss of revenue, if 15% of the post failed, would be $300,000 in lost donations. This is on top of the $15,000 already lost in initial expenditure. Not to mention that, as with emails, complying with legal regulations may often mean that it is extremely important not to send mail to the wrong address, as these mails then may be seen as unsolicited mail. This could result in legal problems for your organisation, such as fines, making the overall losses even greater, not to mention the loss of reputation caused by legal issues. A charity really cannot afford to lose a single person who they know is interested in their charitable work, and the same can be said for most businesses.

We have solutions regarding reference rules for your postal address inconsistencies concerning cities, towns and states for Germany, India, Malaysia, UK, UAE; for regions in France and territories in Australia.

Please do sign up for our service using your email address, Facebook, Google or GitHub accounts. Here is a quick link to our FAQ. You can also check out our range of subscription packages and pricing, and try it out with 500Mb of free data cleaning. You can also view our videos on data cleaning an EPG file and data cleaning a genre column which explain how to use our API. If you would like to contact us you can speak to one of our team by pressing on the white square icon with a smile within a blue circle, which you can find in the bottom right-hand corner of any of the web pages on our site.

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