In October, Google announced new guidelines that went unheard by many email marketers. They released a blog post as well. Yahoo also followed suit.

There’s a lot of misguided commentary about the specifics of it, so today we’re going to break down some of the most important changes taking effect and why you should care.

Main Takeaway: Google and Yahoo's recent guidelines largely reaffirm established best practices in email marketing. However, a key new detail is the public disclosure of a 0.3% spam complaint rate threshold. While exceeding this rate in a single instance won't immediately land you in the spam folder or get you blocked, it's a clear signal of stricter enforcement ahead. Maintaining a consistently low complaint rate is crucial, as repeatedly crossing the 0.3% mark will now lead to more severe consequences than before.

NOTE: This episode is based on my personal knowledge, recent research as well as chatting with top 1% experts. However, I’m not a lawyer and nothing here should be construed as legal advice.

New Email Sender Guidelines
As of Feb 2024: Failing to follow these new guidelines will potentially result in Gmail limiting sending rates, blocking messages, or marking messages as spam. They haven’t made it clear what result is applied to what guidelines. Lots of folks are claiming that any of these will lead to you being blocked by Google, forever. While that’s possible, it’s not likely.

Another misconception I’ve seen from plenty of folks is that this only applies to BULK senders, people with 5k daily email traffic. This is false. While Google wrote a spectacularly unclear and poorly structured document, it is pretty clear that most of the guidelines apply to ALL SENDERS. So if you misread and told yourself this isn’t a big deal because you don’t send 5k emails to Google users per day, you’re in for a world of pain.

Here’s the TL;DR on the guidelines, they are essentially the same 6 for all senders and bulk senders, except bulk senders have a few extras.

All senders 

• Set up SPF and DKIM auth
• Set up forward and reverse DNS records
• Keep spam rates below 0.3%
• Follow RFC 5322 for format
• Don’t use a from @gmail.com account in your ESP
• Add ARC headers, List-id: header

Bulk senders (5k or more emails per day)

• Set up SPF and DKIM auth
• Set up forward and reverse DNS records
• Keep spam rates below 0.3%
• Follow RFC 5322 for format
• Don’t use a from @gmail.com account in your ESP
• Add ARC headers, List-id: header
• Set up DMARC
• Support one-click unsubscribe, and include unsubscribe links

We’d need a whole series to cover all of these so we won’t go into each. You probably should’ve already been following the majority of these in the first place. We had a decent episode that covered authentication, SPF, DKIM and DMARC. RFC standards, ARC headers and one click unsub is generally adopted by most legit ESPs.

I want to focus on 2 key changes that might be misconstrued or require a bit more digging and explanation:

• Spam rates in PMT below 0.3%
• Don’t impersonate gmail from headers

Keep spam rates reported in Postmaster Tools below 0.3%
The biggest one and the one that’s most talked about is the 0.3% spam report threshold. Most senders don’t need to worry about this. If you have been following best practices for email like expressed opt-in consent and making it easy for people to unsubscribe, you don’t have major spam complaints.

But not everyone falls in this bucket, and even if you do, you might not get off that easy going forward. This is especially freaking out people that do bulk outbound/cold marketing using email.

If you’re not already set up using Google Postmaster to monitor your domain and IP reputation and related metrics, do it now. 

This has actually been a common unwritten rule by mailbox providers (MBP) in the past, anything above 0.3% would potentially cause reputation issues. MBP also do plenty of sneaky things like counting the number of inactive accounts that got your email so you can’t dilute the ratio of complaints you get. I think the change here is that it will be more severe now that the threshold is public.

What’s spam rates exactly?
There’s actually some misalignment from experts when it comes to the true definition of this metric.

Based on this Google Postmaster FAQ, the spam rate is

Spam rate = number of spam complaints from Google users / number of active Google user recipient accounts that landed outside of spam/junk.

It makes sense that it's only for active accounts and for emails that landed outside junk because emails in junk can’t be marked as spam again. So if a substantial number of your emails start actually landing in spam, you could see a low spam rate, even though that wouldn’t be positive.

What does this mean in terms of volume sent to Google accounts?
Let’s break down the impact of 0.3% further:

• If you send 10,000 emails in 1 day, you need less than 30 spam complaints
• If you send 5,000 emails in 1 day, you need less than 15 spam complaints
• If you send 1,000 emails in 1 day, you need less than 3 spam complaints
• If you send 333 emails in 1 day, you can’t get more than a single spam complaint

So if your newsletter of 10,000 subscribers is going out in Feb next year, how confident are you that you’ll get less than 30 people marking it as spam?

And if you’re sending cold emails to 50 people per day, how confident are you that you won’t get at least 1 spam complaint? (2% spam rate)

How to monitor spam: Postmaster discrepancies
Regardless of the exact definition, for the sake of the new Google guidelines, the number you need to keep an eye on is the one in Google Postmaster Tools.

We know for sure that Postmaster does not include any other mailbox providers.

Interestingly, it’s unclear if Postmaster includes only @gmail.com accounts or @gmail.com accounts AND Google workspace accounts. I think it’s a fair assumption though that if Workspace data isn’t going to Postmaster yet, it’s probably only a matter of time. So it’s not as easy as segmenting your list by @gmail.com. Sorry.

If you’re thinking, well my ESP gives me complaint data, I don’t need to monitor Postmaster. First of all you should because Google is basing their new 0.3% limit based on Postmaster data. Secondly, you can’t rely on the complaint reporting in your ESP for this. Google doesn’t send spam complaint data to ESPs. So what you see in your ESPs is spam complaints from inbox providers that share that data through FBL (feedback loops), Google does not share this with ESPs.

The only way to monitor this metric (at least for Google’s sake) is to look at your complaints rates in GPMT over the last 120 days.

How have you performed recently? If you have a few spikes here and there in the 0.2%-0.4% I would bet that you’re probably okay. Google is likely to start by penalizing senders who regularly get over 0.3%... the definition of regular is wha...