Deliverability is the ability for sent emails to reach the inboxes of assigned recipients, regardless of whether the emails are opened or not. If the emails do not reach said inbox, it can be said that the email marketing campaign will not have met the established objectives, the campaign will have been in vain since the emails end up in the spam folder.

Companies should avoid having poor deliverability because this means they will be considered spammers or added to blacklists.

Why is deliverability important in email marketing?


Deliverability is essential in email marketing because it is one of the key indicators of campaign management, it indicates with a numerical value the ability to ensure that the emails sent reach their destination.

By having low deliverability, it is possible that the company has a weak reputation and this is a key value that influences the decision of classifying an email as spam or not. In turn, reputation indicates the behavior of an email marketing campaign, so if the reputation is low this is negative for the company.

How to calculate deliverability rate

The most common formula to measure the deliverability rate is

(Valid emails / Total subscribers) * 100

The result is expressed as a percentage.

Factors influencing deliverability

There are various problems due to which sent emails do not reach their destination and are considered spam. Here are some of them:


Being consistent shows a solid campaign. One of the keys is volume but you have to establish the appropriate frequency depending on the campaign.

Inappropriate format

It is necessary to ensure that emails can be displayed correctly on all devices. Try not to create incorrect HTML coding and avoid prohibited keywords.

Low reputation

The reputation of your email identity affects deliverability. If your brand has a problematic history or multiple complaints, this negatively impacts deliverability rate and reputation.

Insufficient contact information

It is essential to clean databases since consumers often create new email addresses. Inactive users are a big problem for deliverability.

Lack of quality

First quality, then quantity. It is preferable to send few emails but that they are of high quality and make sure that the opt-in technology is the one that filters your senders.

On the other hand, it is worth highlighting 5 agents that are essential in the journey that an email takes and, therefore, influence deliverability, so they must be taken into account. They are the following:


It is the agent that decides the subject, the content of the email, apart from the volume of emails to be sent and the frequency. He is primarily responsible for the quality of the contact list and this directly affects deliverability.


A sender with a good reputation, who has not previously been classified as spam or is on blacklists, all this positively affects deliverability. Senders with very recently created domains can alter it.


It is the email marketing platform that is responsible for sending the content generated by the author to the recipient. Said issuer must have a highly reputable platform and excellent infrastructure.


It is the agent that is responsible for receiving the email and decides what to do with that email based on different factors.


This agent also influences deliverability because it analyzes behavior to determine if the email should be delivered. This behavior consists of actions such as having the sender as a regular contact or having read other similar emails previously, among others.

How to improve your deliverability rate

Certain aspects must be taken care of so that the emails reach their destination. Some of them are:

Take care of the subscription process

It is normally thought that the more users you send emails to, the better, but messages should only be sent to those who wish to receive them and have given their consent.

Debug databases

The databases must be cleaned periodically since contacts must be eliminated with successive bounces.

Your subscribers should save you in their contacts

By saving yourself in contacts, most anti-spam filters are overcome. This strategy is very efficient since the provider considers that you are a reliable contact.

Use an email marketing platform with a high reputation

You have to choose a suitable email marketing provider so that the emails reach the inboxes.

Promise something that you will keep and create relevant messages

Valuable information must be sent to users, to know if this information is valuable we must put ourselves in the shoes of the subscribers.