There are two key points to note first:
1. There is a difference between emailing individual consumers and emailing business contacts
2. Email marketing providers (mailchimp, constant contact etc) are very strict about what they allow you to do because they need to be absolutely certain that they won’t get blacklisted by the big ISPs and email providers.
Emailing individual consumers
The UK’s Privacy and Electronic Communications Regulations enacts the EU directive into UK law. In summary what it says is that you cannot email individual consumers without their prior consent. Prior consent means that they have actually “opted-in” to receiving emails from your company, in other words, given you permission.
The confusing part is that you can also email them, according to the UK’s information commissioner, if you have a prior relationship with them. A prior relationship means that they are already a customer for similar products or services from your company or that they have actively expressed an interest in the products and services being promoted in your email, and at the time they were given the option of opting out of receiving emails from you.
Emailing business contacts
The law doesn’t actually cover businesses, but if you are using the likes of mailchimp or other bulk emailing software, they treat all lists the same and so you need to comply with the consumer regulations. If you are emailing directly from your company email address and you are emailing a business contact at their work email address, then technically you can do what you like.
However, I strongly suggest that you follow best practice and only email people with whom who you have had a prior business relationship or contact, and ideally people who have actually given you permission to email them. Everyone receives enough “junk email”. An email is perceived as junk by the recipient if it is not relevant, useful or interesting. Think about what you are sending. If the recipient will think it is junk, don’t send it. Junk is annoying and you are never going to win business by annoying people.
Take care – partnerships are treated like individuals under the law.
In every case:
You must always include an easy way for recipients to unsubscribe from your mailing list – every time you email them.
If someone unsubscribes you must remove their details from your list and stop sending them marketing material.
You must ensure that the identity of the sender is clear and not concealed in any way
Please note that this is my interpretation of the law for general guidance only and should not be regarded as legal advice. Full details can be found at the ICO’s website.