Senders with delivery problems ask about “the rules.” “Just tell us what the rules are!” “If the ISPs would just tell us what to do we’d do it!” There is only one rule anyone needs to pay attention to for good mail delivery: Respect the recipient.
Not good enough for you? Want more specific rules? OK.
The two rules everyone must follow for good mail delivery.

• Send mail recipients expect and want to receive.
• Don’t monopolize resources that aren’t yours.

The secret to delivery is very simple: respect your recipients and respect the ISPs.
Everything else is an implementation detail. Those details are often important, but they’re just details. If you follow the two above rules then delivery will work.
Many people, delivery experts and ISP filtering staff, have very negative reactions to a sender who says “just tell me the rules and I’ll follow them.” But, you say, that’s not fair! If they want to know the rules it’s because they want to do things right! Experience suggest this isn’t true.
People who ask for “the rules” usually don’t actually want the rules. What they really want to know are the specific, hard thresholds they should meet. They want to know what the thresholds are for things like complaint rates and open rates and all the other things that ISPs use to measure reputation and engagement so they can tweak their program to coast along that line. They want to do the absolute minimum they have to do in order to pass. They’re not actually interested in sending mail people want, or sharing ISP resources. Instead they want to know how far they can push things without triggering a negative effect.
They expect an A for effort. If they don’t get the A for effort, then they want to argue the minutiae of the thresholds. They’ll argue with the ISPs. They’ll argue with their ESP compliance desk. They waste hours or days explaining why the thresholds are wrong or shouldn’t apply to them.
Don’t be that sender. Don’t spend so much time figuring out that if you have a 0.12% complaint rate you’ll get to the inbox and if you have a 0.125% complaint rate you’ll get bulk foldered.  Focus on sending relevant, engaging email that people want to receive. Your email marketing program will flourish and your boss will thank you for it.

bulk • complaints • engagement • Relevancy • rules • Spam