Set up DMARC and see who's sending email using your brand's domain.

Best practices to ensure great delivery for your email: Part 3

In this blog series we’ll discuss how we came to the conclusion that manual account approval will help us maintain the best deliverability for all of our customers. In Part 1 we discuss how ISPs establish and track your email’s delivery reputation . Part 2 focuses on things you can do from your side to make sure your email gets delivered reliably . And in part 3 we discuss how all senders share the responsibility for good delivery, and how that led to our decision to move to a manual approval process.

How sharing reputation and responsibility can improve delivery #

As we explored in a previous article, reputation is tied to both your domain and IP address. While your domain is something you own, you’re likely to really only be renting your IP address. Building reputation on your domain helps protect your brand and makes your reputation more portable between providers. Additionally, with the onset of IPV6, IP addresses are becoming increasingly disposable, and so inbox providers are shifting some of the weight of reputation towards domains. Nonetheless, your IP address will still contribute meaningfully to your reputation.

...pushing customers towards dedicated IP addresses is also a means for ESP’s to retreat from their overall responsibility for delivery while charging customers more.

The standard solution for a better reputation and improved delivery is to use a dedicated IP address so that you’re not sharing your reputation with any unsavory senders. While this makes sense on the surface, pushing customers towards dedicated IP addresses is also a means for ESP’s to retreat from their overall responsibility of delivery while charging customers more. A dedicated IP can help insulate you from delivery problems, but it’s not a silver bullet.

There are a few caveats to dedicated IPs that are worth considering:

  1. If you don’t have enough volume to establish a solid reputation, a dedicated IP address won’t help as much.
  2. If you have a significant increase in sending volume in a short period of time, it could hurt your sending reputation. With shared IPs, these sending increases can be absorbed and spread across IP addresses so your reputation isn’t affected.
  3. IP addresses have to be warmed up. If something does happen to hurt the reputation of your IP address, warming up a new IP takes time. You may be limited in the volume you can send for some time while you build reputation on the new IP address.
  4. Dedicated IP addresses usually cost more. Providers advertise really cheap rates for sending, but then ask you to pay extra for “improved deliverability” so the rates aren’t always as appealing as they look. In a way, this also gets them off the hook for delivery by pushing that responsibility on to you. 
  5. If you send  both bulk and transactional, you’ll want multiple dedicated IPs in order to compartmentalize the reputation. So your costs are increased even more.

For these reasons, and others, we believe that a pool of well-policed shared IP addresses is the best bet for the vast majority of senders. Of course, once you reach a point where a dedicated IP makes sense, we can handle that for you.

The key with shared IP addresses is that messages must be very well-policed. This means that bad senders need to be detected ahead of time or shut off quickly when they misbehave, and affected IP addresses need to be taken out of rotation. Moreover, customers should never have to request that their provider move them to a different IP address. It should be the provider’s responsibility to ensure that customers are on healthy IP addresses.

So, what does a shared IP with Postmark mean to you as a sender?

  1. First and foremost, we take full responsibility for your deliverability. If there’s a problem, it’s our job to handle it. If it turns out that it’s a problem that’s not our fault, we’ll still help you troubleshoot and work closely with you to find a solution.
  2. If there is a problem with an IP address in our pool, we can quickly take it out of rotation, and we bear the burden of fixing the problem. You keep on sending without skipping a beat because we won’t leave you sending form an unhealthy IP address.
  3. You share in the benefit of great delivery while simultaneously bearing the burden of maintaining high standards for your email. It’s our responsibility to close monitor abuse and misuse so you can focus on sending instead of worrying about whether something is negatively affecting your reputation.
  4. You can relax knowing that we aren’t pushing deliverability responsibility off onto you by making you pay extra and warm up a dedicated IP address.
  5. You don’t have to bear the burden of warming up an IP address. You can hit the road running knowing that your emails will get there quickly.

At Postmark, we’ve built a community of customers that care deeply about their email and deliverability. They embrace email authentication and only send transactional emails. The way we do this is by being extremely careful about the emails that are sent from Postmark since our reputation, and by extension your reputation, is only as good as the other senders using Postmark.

We all have a shared responsibility to uphold to ensure great delivery, but, as your email provider, we also have a responsibility to you to ensure that you’re surrounded by only the best senders. We take that responsibility seriously, and we have to closely monitor and approve who sends email through Postmark, and that means that  you can always be confident we’re taking the best possible care delivering your emails.

Garrett Dimon

Garrett Dimon

Husband. Father. Tinkerer. Mountain biker. Snowboarder. Used-to-be basketball gym rat.