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Buying data for eMail and eMarketing campaigns

So the decision has been made to buy some data and the job is on your desk. You’ve Googled it and a couple of dozen companies are advertising that their mailing list is up-to-date, award-winning and offers excellent ROI. Every marketer knows someone who bought a dodgy mailing list and felt ripped off, how can you buy the cleanest, most responsive list and avoid hooking up with a cowboy?

1. If it looks too good to be true, it probably is. We’ve all had the emails promising 100,000 email addresses for £199. Don’t be tempted. You’re buying email addresses that have been ‘scraped’ from the internet using software, so will feature defunct, incomplete and generic email addresses such as info@ or sales@. Some of those emails may be spam-traps.

2. eBroadcasting with poor data If you buy bad data, you will run into problems sending out your marketing email. Email broadcasters and email software providers will spot these bargain lists and refuse to take the job. You might send out the emails from your own server thinking that you’ve nothing to lose and hey, even if only 30% are correct, you’ve still had a good deal. However, if you send large numbers of emails to incorrect addresses, you are likely to be identified as a spammer, get your company’s server’s IP address on a blacklist eg SpamHaus. Being on a blacklist will adversely affect email deliverability for everyone in your company. This will affect your personal popularity in the workplace.

3. Budget You’re working to a budget, so think about what details you need to know about each individual (known as data subjects). Reliable data providers price their lists per thousand contacts. The price per thousand goes up depending on how many fields of information you select. Do you need both the email address and the postal address? Watch out for a list supplier’s headline price “as little as 10p per contact” and ask about the added extras such as selections, minimum order, multiple use versus single use and delivery charges.

For the sake of clarity, all Electric Marketing lists include a direct, personal business email address. There is no minimum order. You can use the list as often as you wish for 12 months. We do not charge for delivery or selections.

4. The brief: think about who it is you want to target. Be realistic about the numbers of people likely to fall into the parameters you have set. Remember that mailing lists can only be compiled based on the information people are willing to give about themselves.

5. UK Law does not insist on consent for lists for business-to-business emails Be clear on the difference between the laws governing mailing lists of consumers and mailing lists of businesses. Email lists are governed by GDPR and The Privacy & Electronic Communications (EC Directive) Regulations 2003 (widely known as PECR). If you are emailing consumers, the list must be a consented list. If you are using a consented list, your company name must have been mentioned when the consumer consented to receive marketing emails. This rule means that most consumer email lists have been withdrawn from the market since the advent of GDPR in 2018.

There is greater flexibility for emailing businesses and you are allowed to email any business email address at least once providing the email is about business matters, that your company has carried out a legitimate interests assessment, that your email contains a legitimate interests statement and that you give an option to unsubscribe. If your data subject unsubscribes, you must not email them again.

There are six lawful bases for sending an email to a person; legitimate interests is the basis that most b2b email marketing campaigns rely on.

6. Phone round and get a couple of quotes if you are buying for the first time. Competition in the list market can be keen. The three key questions to ask are:

How is the list compiled?
What is the source of the data?
How is the list updated?


An accurate business-to-business list is updated by telephone or desk research twice a year. Ask for a full explanation.

Beware the term ‘constantly updated’ which is bandied around and is largely meaningless. It can mean that a comprehensive updating system is in place or it can mean that a handful of changes are made to a database of millions of addresses every day. If a list supplier cannot give you a definite time frame when the entire dataset is refreshed, best to walk away.

7. Insist on having some sample contacts (for free).
Ask to see a sample of the data and test it. If the data company won’t give you a sample for free, then buy a small amount. Scrutinise the data sample: is this what you have asked for? Are the contacts in the correct area of the country? Are the addresses spelt correctly? Is the data post coded? It is an idea to match the data sample against your current customer list. The more matches you have, the better the list is likely to perform as you are buying more of the same types of contacts who have already bought into your company's offer.

8. Timing is key. Buy the freshest data that you can and use it immediately. Good data providers can email over data to you within hours so unless you are printing out personalised items for mailing, there is no need to buy early. Deliverability guarantees from your list supplier often only last for 14 days. People move jobs, move offices and change their email every day of the year, which means that every day your list becomes that little bit more inaccurate. Over the course of a year business data can decay by 50%.

9. Check the terms of use for the data. Have you bought it for one-time use only or for multiple-use? Different list providers have different rules on usage. Do check the small print and don’t assume the list provider won’t find out if you use the list more than you should or pass it on to a friend. Lists are seeded with contacts that route back to the list provider. They will find out and you will most likely be invoiced for the extra usage.

10. Bouncebacks Check the deliverability guarantees of your list provider. Some companies offer refunds or replacement contacts for every ‘hard-bounce’ email. A ‘hard-bounce’ is an email address that is rejected by the server because it is incorrect or because the server identified your email as spam. A ‘soft-bounce’ is an email that is not delivered because the mailbox is full or the server is down or swamped with emails or the message is too large. If you received a high number of hard bounces, check the reasons for the bounces by studying the SMTP error codes. If it is down to incorrect data (SMTP error code 5.1.1) then claim your refund for those addresses, but don’t hang about, there is usually a time limit on that too.