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Don’t buy that list!

This is a refresh of an article we wrote way back in 2011. Sadly it’s still relevant.

We get asked fairly frequently by some of our customers about various cheap list providers. These often contain a million or so contacts, and are priced around the £300 mark. I don’t think we can put it any clearer than:

Don’t buy that list!

It all sounds like a great deal, but it’s not. Despite the promises of such data providers, this is junk data and will do you more harm than good. What we’ve typically found with this kind of data:

  • Up to an 80% bounce rate, damaging future deliverability.
  • Massively out of date – we tried contacting several supposed subscribers and found they hadn’t worked at those companies for 10 years!
  • Poor validation – addresses like or are blatantly harvested, and invalid addresses like user@example. can never have completed a double opt-in process, suggesting the provenance of the data is suspect, and the whole list can’t be trusted.
  • If they’re harvested, they very probably contain spam traps that will poison the whole of your list and our service, resulting in all your future mail being blacklisted, blocked, or consigned to spam folders. There is no way of spotting spam traps.
  • No provenance metadata – no IP addresses; date, time and how the address was obtained, date of last mailing. All are legal requirements.
  • Long provenance chains: these lists are often obtained elsewhere from other list sellers. When data is passed around so much, it tends to suffer.
  • No third-party authorisation – without explicit proof, chances are the subscribers did not provide explicit permission for their data to be resold, if they ever opted in at all.
  • No additional data – decent list providers will usually be able to tell you accurately a person’s name, company name, address, home number, and more.
  • Low quality data – If additional data is provided (e.g. if it was obtained from survey sites), it will often contain uncleaned rubbish data, such as first names of ‘asdf’, swearing, hack attempts etc.
  • Large lists are often sourced from survey sites who pay people (nominally, for example in some kind of loyalty points or discount coupons) to complete surveys. Such participants are usually in it for the points and are not in the least bit interested in anything else.
  • If recipients didn’t really opt-in, it’s extremely likely they will be disproportionately annoyed by messages from you, and tell others, twitter, spam reporting services, and their ISPs all about it, dragging any brand credibility you had through the mud in a very public way.
  • These lists are sold over and over again, meaning that anyone who does get mailed on it is probably pretty annoyed with their level of spam already.
  • Bad providers typically don’t ask for or accept bounce data back, meaning they don’t maintain these lists and quality will deteriorate over time.
  • While convictions are rare, if addresses have not been obtained legitimately, you can be liable for a fine of up to €12,000 per message, and jail time in some EU countries (which has happened for a single message in Spain and Germany)!

It’s common for such providers to say “but they’re all business addresses, so are exempt from opt-in”, however, there is no such exemption for business email from the US CAN-SPAM legislation, so you’d need to drop all .com, .net etc addresses to be compliant (and even that is approximate), plus it’s been held (in UK courts) that any addresses on public services such as hotmail, gmail, yahoo and aol should always be considered personal. GDPR requires explicit consent for marketing purposes, even for business addresses, and even if you already hold personal data for other reasons. By the time you’ve knocked those out, there’s probably not much of the list left!

Many supposed marketers still fall for it and say, “well, I might get a few queries, which is worth £300, and I don’t care about the rest”, but this is exactly what spamming is. The net result is this; across-the board reduction in quality and performance for everyone.

A really simple approach before you spend any money with a list provider is to search for their name: if they are bad you’ll find the search results are filled with scam reports and horror stories, so they’re easy to spot. Even “positive” reviews such as “the list only contained 20% bounces” should also set alarm bells ringing – a good legitimate list will have a bounce rate around 0.3%.

Growing and maintaining good quality lists is difficult and expensive, so don’t expect to get such data cheap. As in many scenarios, if it seems too good to be true, it’s probably a scam. There are good list providers, but you won’t find them in the same cost ballpark as these bottom-feeders.

So that’s why we don’t accept bought-in lists, and why you should be trying to use them either. Not surprisingly, most other ESPs have the same rules.