Companies send out two very distinct, very different types of emails (or at least, they should).

Transactional (or business) emails relate to the specific individual: welcome emails, invoices for payment, lost password requests, scheduled system downtime and the like.

Marketing (or newsletter) emails relate to things that the individual might find interesting such as new features, opinion pieces from your blog and new features.

It’s about reputation – baby!

Mail providers use something called a sender reputation score to determine whether or not to display your emails to the recipient. Just because an email displays as “sent” on your side, doesn’t mean that the recipient actually received the email. The reasons behind this are all rather logical: they are in place to make sure that spammers (and dodgy operators in general) will lose reputation and you won’t be bombarded with unwanted mail (which will either never appear or show up in your spam box).

I won’t go into it too much, but your reputation is based on two things: IP reputation (or server reputation) and domain reputation. Some ISPs focus more on one, some more on the other, so it’s a good idea to think of your reputation holistically.

Things you should consider

Different mail providers have different standards, but there are a few things that are very important to keep your reputation high:

A squeaky clean server

Don’t ever bother signing up with a dodgy mail operator. If you are on a shared hosting environment and use the same servers for email, you’re looking for trouble, since other people might send spam from other websites on that server.

If you don’t know where to start, sign up with MailChimp for marketing email and Sendgrid for transactional email. They know what they’re doing, provide good support and have thorough documentation to help you do things right.

No spam complaints

While you’ll never be able to completely control this, you need to try and avoid spam complaints as far as possible. This means two things: 1. Write meaningful content and 2. Make it easy to unsubscribe.

The more relevant (or value-adding) your marketing messages are going to be and the more control you give your user, the fewer spam complaints you’ll have.

You should also give your users the option to opt out of certain types of transactional emails, as Twitter allows you to do:

Content

Sending out large attachments (or certain types of attachment), having suspicious subject lines (or content) and badly formatted HTML emails all could lower your reputation.

If you’re using a quality email service to compile your emails, providing valuable content and not trying to push Viagra on people, you should be good.

Segment, segment, segment

Segment your email recipients as much as is reasonably possible.

If you sell three types of products (say cloud backup software, booking software and e-commerce software), you don’t want to tell hotel owners (using your booking software) that there has been a version update to the e-commerce platform.

You don’t want to send a newsletter about changes to online shopping delivery laws in your country to everyone/if it doesn’t relate to the cloud backup users.

You could –depending on your business— further segment your subscribers (for marketing mail) and users (for transactional mail) by location, industry and the like. This will help greatly in refining the value-adding message for the recipient.

Use different email addresses (but don’t go overboard)

Some companies use different domains to distinguish between their marketing and transactional mail, but this is, in my opinion, a bad idea.

Simply create separate email addresses like noreply@yourdomain.com (for transactional mail, which/if it has to be delivered) and insight@yourdomain.com (for marketing mail).

With modern mail applications, you can set separate reply-to addresses (so if someone replies to your newsletter email, that it goes to something like support@yourdomain.com)

This helps your customers to filter your emails. Users might want to add an email filter on your newsletters, since that kind of information isn’t critical to operations (I like to keep a clean inbox and get to my newsletters when I have downtime).

Don’t make the mistake of sending emails from too many “from addresses) like using the first names of every newsletter contributor. It might give it a personal touch, but if the recipient has added tom@yourdomain.com to her address book, particularly when it’s filtered it so that all emails from “Tom” should go to her newsletter/social inbox, you’re going to piss her off when you clutter her inbox with an unfiltered email from steve@yourdomain.com and mandy@yourdomain.com. 

Authenticate! Use DKIM and set an SPF record

I should have mentioned this first, as it is one of the most important things to help show the recipient’s mail provider that you’ve authorised certain servers (say, those of Sendgrid) to send emails on your behalf.

You’ll notice that some emails (usually marketing emails) you receive have the “sent via somedomain.com”. Here’s a blurb by Google on it.

In some cases, the mail might even end up in your spam folder with a warning from your mail provider saying that they couldn’t verify the sender of the email. The following email (from the otherwise superb Buffer)

It’s a remarkably simply fix, you’ll simply need to reach out to your email (or hosting) provider and ask them (or do some light browsing through their documentation).

Two blurbs by Google: the first on Sender Policy Framework and the second on DomainKeys Identified Mail.

Testing

You can check your reputation free on SenderScore (should be taken with a grain of salt, as not all mail providers use the same formulas)

To test a whole range of things associated with your domain, check out the excellent MX toolbox.

In closing

Authenticating your email can be a little complicated, but it is a necessary step to make sure your emails get delivered. Make sure that you use a reliable/clean server to send messages from and always give people a way to opt out of your marketing messages (and if possible, a way to control the amount of transactional messages).

Lastly –and this should be at the core of what you do; not just your emails—only create and share things if they add value.

Email is a tricky thing to get right and you can go down lengthy wormholes to get things right, but it is far cheaper to get it right right now, than to spend the extra time and money (and lost resources) by having mails go unread or servers blacklisted.