The following is a guest post from Jesse Wynants at Prezly. Learn how Prezly has leveraged SendGrid to send email on behalf of their users as part of our Marketing Solutions Partnership below, and learn more about Jesse and Prezly at the conclusion of the post.

We’ve been using SendGrid since June 2011 to send email on behalf of our users. This means that users use our service to send email, but their own email address is in the FROM address. (Essentially, SendGrid provides the backend email infrastructure, while we provide our frontend PR services.)

Sending emails on behalf of users adds an extra challenge. You don’t want spam filters blocking your email because they think you’re spoofing an email address. To prevent this, we’ve used and implemented a few techniques that are essential if you’re sending out emails on behalf of your customers. I’ll share a few of them below.

Ask Your Users To Set Up SPF and DKIM

If you want your users to send email from their own FROM address, (also called sender authentication) like we do, SPF and DKIM are the fix for telling spam filters that it’s “ok” that the SendGrid mail server can send emails on behalf of a domain. This is one of the most important steps, but unfortunately, a complex one, so you need to make it as simple as possible.

The records your clients need to configure are exactly the same as the ones you configured in Domain Authentication. You can find these records in the SendGrid documentation.

1. Make it as easy as you can for your customers to configure SPF and DKIM themselves


Depending on how tech-savvy your users are, they can do it themselves in your backend.

2. Make sure you validate the SPF and DKIM settings

One thing that’s worse than no SPF and DKIM records are badly configured SPF and DKIM records. Make sure you validate the domain records on your end before activating them.

3. Make it easy to share the domain record details with their IT team

Most of the time, your users aren’t the ones who have access to the sending domain. They’ll need to go through their own IT department to get the domain configured. It helps if you have an easy-to-access documentation page they can refer to. We even proactively get in touch with IT departments to make sure they have everything they need. This seems like a lot of work, but helping your users succeed always pays off in the long run.



Guard Yourself From Abuse

If people are using your service to send their emails, you need to make sure you have some good control systems in place. We have a few of these checks that were helpful for us below:

1. Put a limit on the number of emails they can send

People signing up for our trial service can’t import more than 5 contacts by default. This means they can’t sign up, import thousands of contacts, and blast emails to them. This limit gets removed on request, after a manual check-up of the user and their contacts. It’s a simple, powerful trick to keep spammers away.

2. Manually follow up with spam reports

All the spam reports coming in are being forwarded to my personal email address (you can do this using the Forward Spam app). I follow up with each spam report manually by getting in touch with the user and notifying them of the report. A personal email to the user shows that you’re keeping tabs on their sending behaviour. At the same time, you can keep an eye on your global deliverability rates. If this manual follow-up becomes too much to handle, you and your users may be doing something wrong.

3. Keep an eye on your email volume

It’s logical that if your service adds more users, your email volume grows. But the growth should follow the growth of your userbase. Checking your daily volume will give you a good idea of your daily volume and will make it easy to spot inconsistent behaviour. We use Unique Arguments in the SMTP API to pass on user IDs to SendGrid, which allows us to match each email going out to a user.

Educate Your Clients on Improving Their Email Deliverability

This often seems like an optional step, but don’t fool yourself, it’s as essential as any other. The fact that you’re reading this is a sign you know more about email deliverability than your users. You’ll ultimately be the one that needs to convince them that following deliverability guidelines will pay off in the long run. The better they follow best practices, the better their deliverability rate.

1. Make sure you’re up-to-date

Email deliverability is a mix of constantly changing factors that you need to know: best-practices, laws, and technology all come into play. If you’re not aware of these things, you can’t expect your customers to be. I would suggest adding this blog to your reading list, or if you want more, you can join one of the excellent SendGrid webcasts about email deliverability.

2. Give tips and tricks when they’re using your service

Track the behaviour of your users in your service and make them aware of bad behaviour before they hit send. Focus on helping them become more successful at the task at hand instead of just saying “What you’re about to do is wrong.”.

3. Don’t tolerate bad behaviour

If some of your users are ignoring best practices, you should ask yourself if these users are a good match for your service. We’ve declined potential customers on occasions because they had the intention of ignoring best practices. At first this seems to be costing you money, but in the end it will pay off.


Email deliverability is always going to be a work in progress. You can’t just fix it once and never think about it ever again, but I hope these tips can help you manage your deliverability in the long run. Good luck.


About Jesse and Prezly: Jesse Wynants is co-founder at Prezly, a PR tool that helps you pitch stories to your media contacts that care. Follow Jesse on Twitter or connect with him on LinkedIn.


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