Once the warm-up is complete, you can start to gradually increase the number of outgoing emails and the delay between them (we will get to that later). For example, here’s a sample framework you can use to ramp up your outreach.

It’s also best to keep sending small amounts of those warm-up emails to balance out the cold ones even when you reach the desired results to further protect your reputation.
BONUS TIP: Get yourself off the blacklists
If you’re finding your email delivery rate is through the floor, then you may have inadvertently ended up on one or more blacklists. Some are specific to major ISPs, while others are publicly available. Tools like mail-tester.com will check the most popular blacklists and provide you with the list.
If you have found yourself on a blacklist, don’t panic just yet. Some will automatically remove IPs once they are no longer associated with spam activity. Others will have a procedure you can follow to get yourself removed.
Keep your list clean and up to date

If you bought your list from some suspicious dude in an alley, it could be costing you more than you think. By sending out your emails to a stale, unverified list, there’s a good chance those addresses are out of date if they were ever genuine in the first place.
Some ISPs and blacklist providers set up spam traps as a honeypot for attracting spammers. But even if you’re not emailing spam traps, having out of date addresses on your list can also be harmful:
Out of date addresses lead to bounced emails.
Bounced emails lead to a damaged sender reputation.
And lots of bounced emails? That leads to a lot of damage to your reputation (and possibly the dark side of the force).
So, review your list regularly and weed out bounced and inactive contacts.
If you’re emailing a double opt-in list full of people that signed up specifically to receive emails from you, you may think you don’t have to worry about this. But it’s still important you keep these fresh too.
For example, if you’re not emailing people regularly, they may forget who you are and incorrectly report the message as spam. If you start seeing hard bounces come back from your campaign, get those addresses off your list straight away.
For cold outreach, it’s best to have several smaller contact lists targeting different audience segments with tailored, relevant messages. For example, you can have separate sequences based on ICP, industry, company size, role, location, or even specific buyer intent the prospects have shown.
Watch your content

Assuming your email is a legitimate commercial email, it’s still good practice to make sure the content of your email isn’t setting off any alarm bells.
As an obvious example, putting “cheap Viagra” in your subject line or email is going to raise alarm bells and dump your email into the junk pile. The same goes for talk of free, offer, buy now and subjects in ALL CAPS or with lots of punctuation!!!??.
Some other less obvious examples of words that are on the naughty list include Oprah, Dear, and Extra Inches. While filters are getting smarter and better at differentiating genuine emails from spam, there’s no reason to use keywords that make your email look like spam.
Our Email Quality Check feature is just what the spam doctor ordered for highlighting potentially harmful worlds in your templates and giving data-backed suggestions on a few other parameters (positivity, readability, number of questions, etc.) to improve your email copy.
All good emails should be written for humans first and foremost, but also take a moment and think how a spam filter might interpret your subject line and email. You might be talking about how we can expect a few extra inches of snow this year, but the filters might just see a massive red flag.
BONUS TIP: Don’t get carried away with images
A picture may economically paint a thousand words, but if you’re relying on images you could be in trouble. When spammers realized filters were flagging their keywords, they started using more images in their emails. In response, although the filters couldn’t tell what was in an image, they started flagging messages with a high ratio of images to text as potential spam.
So, while you may think all those pictures are great and showcase your product perfectly, they could be hurting your delivery rate, even if your message is completely legit. That’s why we recommend maintaining a healthy text to image ratio of 80:20 or higher.

The same goes for emails using excessive or broken links, HTML elements, or even formatting (exclamations or bold font).
Follow a consistent sending schedule
When talking about the outreach schedule in terms of email deliverability, there are two key aspects to keep in mind: email throttling and sending delay.
Throttling refers to sending limits, i.e., the number of emails you can send from your email account per day/minute without raising any red flags. The number mostly depends on your ISP.
For example, Outlook sets the limit for 30 emails per minute (and just 1,000 daily recipients when talking about the ones you’ve never sent email to). For Gmail, the limit is 2,000 emails per 24 hours.
As for the sending delay, it’s the amount of time allowed between each sent email. We recommend at least a 30-second (optimally – a 60-second) delay between each email sent to avoid your account being blocked for spam activity.
Luckily, most sales engagement platforms, including Reply, allow you to manage these settings. As a result, if you launch a campaign for 1,000 recipients, not all 1,000 emails will be sent at once. Your SEP will send those emails over a certain period of time to make your schedule seem more natural (as if you send every email manually) and avoid triggering spam filters.
Send an email that matters

This may seem a bit backward. Surely there’s no point worrying about the quality of your message if it’s never getting delivered in the first place, right? Well, beyond the obvious point of avoiding spammy tactics, quality emails can have other advantages.
For a start, valuable emails are much less likely to have complaints raised against them or be reported as spam. Going deeper, some spam filters will flag messages based on engagement levels.
If your message has been read, replied to, or forwarded, that sends positive signals that the message is welcome and not spam. On the other hand, unread messages send a negative signal and might lower the rate of delivery for your next emails.
By sending emails that provide clear value, you’ll get better engagement from your recipients, reduce the chance of being incorrectly flagged as spam, and improve your delivery rate.
That is why we recommend aiming at the following results with your cold outreach campaigns:
- bounce rate lower than 10%
- open rate higher than 20%
- reply rate at least 2-5%