Bulk sender requirements

Bulk sender requirements are a set of technical rules and best practices that email service providers (ESP) use to reduce spam and impersonation attempts (phishing).

Basically, to protect their users and make sure they only receive the emails they want to receive.

If you send email campaigns, you should always comply with these requirements, as the deliverability of your campaign, and its results, depend on it.

· Quick checklist of bulk sender requirements:

As a reference, let’s first share a quick checklist of the requirements:

• Authentication: SPF, DKIM and DMARC.
• Consistent domain in the “From” and DMARC alignment.
• Easy unsubscribe option and, when applicable, one-click unsubscribe.
• Maximum spam complaint limit: 0.3% reach this percentage and it is very likely that your emails will end up in spam or your domain will be blocked
• Maximum bounce limit: a volume higher than 2% would indicate an old or purchased contact list, which damages the sender’s reputation
• Unsubscribe link available: it must be possible to unsubscribe easily and immediately

There are a few more requirements, such as the correct message format, but that is usually handled by the email marketing system transparently for you.

So the important thing is to focus on the rest of the points.

What are these bulk sender requirements for?

As we’ve just mentioned, these sender requirements for bulk mailings are mainly used to decide whether the destination servers (Gmail, Yahoo!, Outlook, etc.) trust your emails or not.

In practice, these requirements ask two things of you.

On the one hand, these settings confirm that your sender is who they say they are, and on the other hand, that you send email your recipients actually want, not spam.

This is why bulk sender requirements combine authentication and recipient behavior, as we will see.

What does this mean?

That it’s not all about the settings; your contact list and the content you send also matter.

A lot, actually.

Why these bulk mailing requirements exist

The different email providers (Gmail, Outlook, Yahoo!) want to make sure their users receive only the emails they want to receive.

Although we might think otherwise, the volume of emails sent keeps growing:

• 2018: 281.1 billion emails sent/received per day
• 2022: 333.2 billion emails sent/received per day
• 2024: 361.6 billion emails sent/received per day
• 2025: 376.4 billion emails sent/received per day

With this increase in volume, email providers have more work than ever to keep out spam and/or phishing emails.

Hence the need for these filters.

If they didn’t exist, users would receive emails they don’t want and would stop using these providers.

Of course, complying with these guidelines helps your mailings reach the inbox, improving your statistics.

Who do bulk sender requirements affect?

In principle, they mainly affect senders who send volumes of more than 5,000 emails per day.

Important!

Once your sender reaches that limit at any point, it will be considered a bulk sender forever, even if subsequent mailings are lower in volume.

If you send less, don’t you have to comply with these requirements?

The truth is you do, and you should also watch spam complaints and bounces whatever volume you send.

How to implement bulk sender requirements?

With Mailrelay it’s very easy: you can go to the Settings – Email authentication section and there check the settings for:

• SPF
• DKIM
• Dmarc
• And custom domain

Which are required.

Then, in the bulletins and newsletters you create, you can add the unsubscribe link block to meet this requirement.

And of course, if you have any questions, you can count on our support team at any time.