The ultimate guide to killing spam

At Growbots, we believe the key to a successful outbound program is a strong focus on quality. If you find people who probably need your solution and you send messages highlighting your value to them, it will not be considered spam. In this tutorial, you can read both how to keep high standards and what to do in case it’s too late and you’ve already got blacklisted.

Targeting the right people

The key to starting a successful campaign is to know who you want to contact and why. If you reach out to the right people, there is a higher possibility they will be interested in your product. When you send out emails to random prospects, they will consider your messages irrelevant and mark you as spam.

Find your market-fit

Before starting outbound campaigns, you should define your ideal customer profile – determine which industry potentially has the best companies for you, how many employees they have or where they are located. It’s also important to know what decision-makers are usually interested in your product – don’t contact technology directors if your product will be used by salespeople. If you are not sure who your perfect customers would be, analyze your current clients, check what they have in common and why they use your product. This is an easy way to find a market fit.

After a campaign, analyze positive and negative replies. Check who was interested in your product, find what these prospects have in common. Negative feedback can be even more precious than positive – collect reasons of no interest in your product and validate your ideal customer profile.

At Growbots, you can define as many target groups as you wish. Create various projects and test different criteria. Before accepting the list and scheduling messages, review the generated contacts and reject the ones you do not want to contact. The more precise you are with the prospects’ selection, the higher the chance your message will be well-received.

Bringing real value

Know your prospects

When you find people who may be interested in your offer, use your knowledge about them and adjust messages to their needs. You should know what problems they encounter every day, so try to show how your company can help. Take into account that C-level and managers meet various obstacles and have different expectations. Don’t be “that” salesman. Write your message like one friend to another, without pushing. Then read it again and ask yourself whether you would like to receive such an email. It’s also great when you are able to find something in common with your prospects – leverage this to help make people interested in your message. If they see the information is relevant, they will not mark you as spam.


You cannot do outbound without follow-ups. However, remember to respect the prospects you are contacting and do not send messages too often. Don’t send emails every two days at the same time. The first follow-up can be delivered after 3 days, but keep longer pauses for the next ones. Time differentiation has more advantages – it’s possible that some people have meetings every day at 9am. If you send them messages at a different time, there is a higher possibility you catch their attention.

Make the communication user-friendly

It’s also important to write your messages in a casual style. Avoid inserting too many links, especially shortened ones such as and attaching files or pictures. The more sophisticated your formatting, the higher chances that some spam filters will catch your messages. Be aware of the fact that some words and expression can automatically mark you as spammers – “offer” or “free” will not escape the spam filters.

Always give an opt-out option and don’t bother anyone if s/he doesn’t want to get any more messages from you. Take care of invalid email addresses – try to have your bounce rate as low as possible. At Growbots we always prevent additional communications once a new reply is received. We also work to keep the bounce rate under 10% to make sure your domain is safe.

Avoid getting blacklisted

Sending multiple campaigns

Outbound messaging is a great way to grab a lot of warm leads without spending too much time. However, it doesn’t mean you should do it without any strategy – each email operator has some daily limits, e.g. in Gmail it is about 200-300 emails per day. If you need to send more emails, we recommend creating multiple channels like or and sending only 100-130 messages daily from each one. Even if you send messages from different email addresses, try to have about 1.5h pause between the batches. Schedule the first campaign for 9am, the next one for 10:30am, then 12:00pm etc. – spam filters not only check how many messages you send from one channel, but how many are sent from a single domain.

It is also worth to switching between different messages. Try not to send the same email campaign two times in a row from one domain. If one of your templates is extremely successful and you want to use it the most, prepare two versions of it for each email channel. It’s enough to rewrite some of the sentences using synonyms. The results will be the same and you will avoid being caught by spam filters.

A good practice is to use custom fields in the subject line, e.g. {{ first_name }} – this almost makes it look like each message is sent with a different subject and won’t look like an automated email.

Take care of your domain

It is very important to take care of your domain and to not spoil its reputation. When you do outbound, a good idea is to have more domains, e.g. and Since they are two separate entities, you could send two batches of emails at the same time. Also, with the domain being less important you may do more risky tests, try different target groups and campaigns.

When you create a new domain, you need to use it for some time and let it build up its reputation. Send emails to your friends, existing customers and wait for their replies. Once you create a natural traffic, you will be ready to start doing outbound.

Keep your finger on the pulse

Even if you do your best to avoid being marked as spam, you still need to monitor it constantly. The easiest way is to keep an eye on your open rates. If you notice a sudden drop, it’s time for more advanced analysis of your mailbox. Check if you were caught by Gmail Spam filters, send a message to any a Gmail address which you haven’t been in touch with yet.

There are also a lot of websites and tools you can use to check your sender score. We recommend which offers a deep analysis of both your message and your mailbox. Here you can check how the content you send is assessed by spam filters and whether your server, IP address or domain are authenticated. The test also verifies if you appear on any of the 22 most common blacklists. Do not panic if you notice your score is not 10/10 – anything over 7/10 is a really good result. Always analyze where you lost your points and try to improve on your weaknesses.

For more information, please refer to the comprehensive guide to using mail-tester.

When it’s too late…

Getting off of blacklists

It may happen that your IP address or email gets blacklisted. It’s not the end of the world, but you should do your best to be removed from it. Each blacklist has its own procedures on how to get de-listed. The most popular ones are self-service and time-based removal methods. When you know the name of the blacklist you are on, you should find information how to proceed with it – maybe it’s enough to wait one or two weeks. When you appear on a blacklist for the first time, its not that complicated to be removed. However, after you are listed once, you need to be much more careful. Being listed for the second time will cause a lot of troubles and the removal process becomes much more complex.

It’s worth keeping in mind that there are not only blacklists but whitelists too. Appearing on such a list shows that the IP address/domain is trustworthy and let all the messages be delivered.

Improving your mailbox reputation

When you notice you have been caught by spam filters and it turns out it is too late for the preventive methods, you need to work on your mailbox reputation. Collect your friends’ and workmates’ email addresses – the private or the business ones to which you haven’t sent emails before. Send them messages and ask to reply to you and mark you as not spam. This will improve your reputation and let you send emails again. You should perform such action every time your score is not satisfying. Remember about sending messages to the new addresses only – emails to the people with whom you’ve already been in touch will not do the magic.


The key to success in outbound is to base your strategy on sending high-quality communications which adjust to your recipients and brings them value. Being aware of your potential customers’ needs lets you adjust the messages you send and offer them a helpful solution. It may happen that you are caught by spam filters or blacklisted but this is not the end of the world. Work on your domain and IP address’ reputation and keep the standards of your communication high in the future.

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