How to Maximize Your Delivery Rate in 2025: The Go-To Guide
Oleg Campbell03 Jan 2025
Thanks to its incredible ROI and relative ease to set up, email has become a key engagement channel for most of today’s sales and marketing teams. However, before you can see the results from your outreach campaigns, your emails have to actually be delivered.
According to the Radicati Group estimates, the total number of business and consumer emails sent and received per day reached 319 billion in 2021. And this figure is expected to grow to over 376 billion by 2025.
While spammers get sneakier and people become more protective of their inboxes, it’s easy for even the most ethical outreachers to find their emails bouncing. So how can you ensure your carefully crafted message doesn’t fall victim to the spam filters and end up in the wastelands? How do you get your email campaign off the ground and into your prospect’s inbox? And what is a good email delivery rate in general?
Read on to learn how to maximize your email delivery rate and avoid common mistakes.
What’s email deliverability and why it matters
Spending hours to build your personalized, tailored email sequence just to get a “no” is exhausting but not irreparable. You can turn almost any objection around. Knowing that your emails haven’t even reached the prospect’s inbox, vanishing into the spam folder or bouncing back, is much worse.
Deliverability is the probability of your emails actually being delivered to the intended recipients.
One of the key email marketing metrics, it is also often referred to as inbox placement. In this case, however, we’re talking about the email being delivered to the inbox rather than the spam folder.
Deliverability or email delivery rate is a slightly broader term that includes the technical aspect of “delivery” to the given address, regardless of where the email actually ends up — the inbox, spam, or Promotions folder.
5 reasons why your emails won’t reach the prospect’s inbox
The chances of your email being delivered to the recipient usually depend on a number of factors.
Here are some of the most common problems that may harm your deliverability rate:
Authentication problems or technical issues with your emailing server
Weak sender reputation, as in the case of a newly created email account or lack of engagement with the previous campaigns
Poor list hygiene — sending emails to invalid addresses or falling for spam traps
Triggering spam filters with your content or sending patterns
Getting flagged as spam by the recipients (e.g., if your emails are completely irrelevant or misleading)
Luckily, most of the listed problems can be solved! Let’s explore the proven email deliverability best practices to make sure your emails hit the target.
9 strategies to boost your delivery rate
Sending an email is a no-brainer. Setting up a whole sequence might take a few hours, but is still relatively easy. Yet, there’s no guarantee that those emails will actually reach the recipient.
Deliverability is a tricky issue that requires a ton of effort and takes some time to build up. Knowing the common blunders that hurt your inbox placement and potential areas of improvement can significantly simplify and speed up the process.
Here are the top 9 aspects of high email deliverability to keep in mind when setting up your outreach.
Comply with the regulations
Like trying to get in a fancy club with no shirt or shoes, some people blast out their emails without any concern for what the rules are. You may think you’re a free spirit with no time for any restrictions but, just like that fancy club, mailboxes have their rules.
If you don’t respect them, you’re not getting in. While it can be tricky and time-consuming to work out the various rules, you can make sure your email is off to a good start with some basic rules of thumb.
To start, make sure your email won’t be legally considered spam. The CAN-SPAM act spells out the requirements for companies sending commercial emails to recipients in the USA.
Tell recipients how to opt out of receiving future emails from you.
Honor opt-out requests promptly.
Monitor what others are doing on your behalf.
If you’re not following these rules, you have more to be worried about than the delivery rate; each separate email breaking the rules is subject to penalties of up to $40,654. Ouch!
Technical setup is the first step to take before you put together your outreach sequence.
For starters, consider your address. You’ll want to make sure the “from” address on your emails matches your sending domain. You’ll also want to avoid using free emails (such as Hotmail, Outlook, or Gmail for example) for sending bulk commercial emails if you want to avoid being flagged. It’s best to use a business email, e.g., [email protected], to do your outreach (with Reply, it’s a must).
We also recommend using dedicated subdomains for your email campaigns to protect your main domain from any risks. For example, if your business domain is business.com, you can use related options like getbusiness.com, business.io, businessteam.com, etc.
Proper authentication is another important step that will ensure high delivery rate. This includes configuring the key domain settings:
In a nutshell, the setup procedures might differ depending on your domain hosting provider, so check in with them for official instructions. There’s a pretty exhaustive breakdown of the most common authentication issues (along with the tips to resolve them) in this article.
Deliverability on Autopilot
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Still asking, ‘How can you improve the delivery of your message?’ I have a simple answer: segmenting your email list. It isn’t just a marketing buzzword—it’s one of the most practical ways to ensure your emails actually reach your audience’s inbox.
Think about it: sending the same message to your entire list is like shouting the same thing to a crowded room, hoping everyone will pay attention.
Instead, segmentation lets you tailor your message for smaller, more interested groups, which boosts engagement and keeps email providers happy. Here’s how to do it effectively:
1. Start with the basics: Demographics
If you have information like age, location, or gender, use it! For example, if you’re a clothing retailer, you wouldn’t want to promote winter coats to customers in Florida in July. Instead, segment your list by location to ensure your content aligns with their weather.
Similarly, age-specific promotions (like student discounts) should only go to the right audience.
2. Segment by engagement
Not everyone on your list is equally engaged. Some subscribers open every email you send, while others might not have clicked in months. Break your list into categories like:
Highly engaged: Opened an email in the last 30 days.
Semi-engaged: Opened an email in the last 90 days.
Dormant: No opens in 90+ days.
For dormant subscribers, you could send a re-engagement campaign like, “We Miss You! Here’s 20% Off Your Next Order.” If they still don’t respond, it might be time to clean them off your list.
3. Use behavioral triggers
What your subscribers do (or don’t do) on your website is gold for segmentation. For example:
Abandoned carts: Send a follow-up email with the items they left behind.
Purchase history: Recommend similar or complementary products to what they’ve bought before.
Browsing behavior: If someone spends a lot of time looking at your blog posts on healthy recipes, send them your next newsletter on meal prep tips or a product that aligns with that interest.
4. Preferences are powerful
Ask your subscribers what they want! When someone joins your list, include a quick preferences form. Do they want daily, weekly, or monthly updates? Are they more interested in product launches or industry tips?
By delivering what they’ve asked for, you’re much more likely to stay out of the spam folder.
5. Reward your VIPs
Not all customers are created equal, and that’s okay.
Identify your top spenders or most loyal customers and create a “VIP” segment. Send them exclusive perks, early access to sales, or sneak peeks of upcoming products. This not only builds loyalty but also increases open rates (and, consequently – your deliver rate) for that segment.
6. Test, tweak, repeat
Segmentation isn’t a “set it and forget it” strategy. Pay attention to what works and what doesn’t.
For instance, if you notice that your “highly engaged” group is suddenly ignoring your emails, revisit your subject lines or frequency. Keep experimenting until you find the sweet spot.
Build and maintain your sender reputation
Joan Jett may not have given a damn about her bad reputation, but if you want your email to be delivered you can’t afford to have the same attitude. With filters placing much more importance on sender reputation today, you need to keep yours as clean as possible.
First of all, filters place great importance on how long the sending domain has been active. As spammers will often try and get past filters by regularly changing the IP address or the domains their emails come from, spam filters now view this as a potentially suspicious activity.
For that reason, you should ensure a proper email warm-up. Simply put, this is a set of activities aimed at building up positive sender reputation. This mostly includes sending emails to trusted email addresses (like your friends or colleagues) and having them open your messages, marking them as important, responding to them, and even taking them out of spam if needed.
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).
Choose the best time to send your emails
Timing is everything when it comes to email marketing. Even the most beautifully designed email with the perfect message will fall flat if it hits your subscribers’ inbox at the wrong time. So, how do you figure out the best time to press “send”? Here’s a simple, practical guide to help you nail it:
1. Know your audience’s routine
Think about your subscribers’ daily habits.
Are they sipping their morning coffee at 8 AM, scrolling through their inbox before work? Or are they night owls who check their emails at 10 PM while winding down? Match your send time to their lifestyle, for example:
If you’re targeting busy professionals, aim for early mornings (6–8 AM) or lunchtime (12–1 PM). These are peak times when people are likely to check their inbox.
For a younger audience, evenings (7–9 PM) often work better since they’re more likely to browse casually after work or school.
2. Consider time zones
If your list spans multiple time zones, this step is critical for improving your email delivery rate. You don’t want to send an email at 8 AM only for half your audience to receive it at 5 AM (when they’re still snoozing). Use your email platform’s time zone scheduling feature to send emails at the local time for each segment.
3. Test different days
Not all days are created equal when it comes to email success. Here’s a quick breakdown of what usually works:
Tuesday, Wednesday, and Thursday: These are prime email days. People are settled into their week and more likely to engage.
Monday: People are swamped catching up, so engagement might dip.
Friday: Hit or miss—great for casual content like weekend deals but tricky for professional updates.
Weekends: These can work for niche audiences (like families planning activities or hobbyists catching up on personal interests).
Pro Tip: Test a couple of different days to see what resonates with your audience. Maybe your subscribers love a Sunday morning email!
4. Send time for specific goals
The best time to send often depends on what you’re trying to achieve:
Promotions or sales: Send emails in the morning (8–10 AM) when people are fresh and more likely to shop.
Newsletters or blog updates: Lunchtime (12–1 PM) works well since people might browse during a break.
Events or webinars: For reminders, send one 24 hours before and another a few hours before the event.
5. Use your data
Your email marketing platform is packed with insights about how to improve deliverability rate (like Reply)—use them! Look at your open rates and click-through rates by time and day to see when your audience is most active.
If you notice most of your opens happen in the evening, adjust your schedule accordingly.
Also, A/B test send times. Send the same email to two segments at different times, then compare the results. Keep experimenting until you find your sweet spot.
6. Avoid rush hours (unless it’s your strategy)
Everyone loves sending emails at 9 AM sharp—but so does every other marketer. Consider going slightly off-peak to avoid getting buried in a crowded inbox. For example, instead of 9 AM, try 10:17 AM or 3:13 PM. Those little shifts can make a big difference.
And rememeber, that there’s no magic “one-size-fits-all” time to send emails, but with a little observation and testing, you can discover what works for your audience.
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.
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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%
Conclusion
SPAM filters are getting smarter and people are getting more annoyed by irrelevant, mass cold emails every day. As a result, deliverability is a lifelong battle for most outreachers.
The good news is that there are plenty of tools that you can rely on in multiple aspects of outreach from contact validation and email warm-up to polishing your content, managing your sending schedule, and watching your metrics in progress.
What’s even better is that there are platforms like Reply that offer all of the listed tools off the shelf to ensure high deliverability of your campaigns.
