Black Friday 2025 deliverability guide

Getting your subscribers' attention in a crowded inbox is a challenge at the best of times, and when it comes to Black Friday the competition is even fiercer!

To make sure that you get the most out of Black Friday 2025, Ometria's Deliverability Team have put together this guide to provide both marketing and technically led advice. 

It covers five steps for great Black Friday deliverability:

• Building your send volumes slowly and early
• Re-engaging your lapsed segments
• Protecting your most engaged subscribers
• Sending at the right time
• Getting a head start on your competition

Background

First thing’s first: the science part. 

Email providers like Gmail and Outlook monitor email traffic looking for consistent sending volumes and engagement from subscribers. 

When they identify spikes in emails going to addresses that don’t normally receive or engage with the emails, they might view the activity as potentially spammy, as it mirrors the behaviour of spammers and fraudsters.

This means the email providers might block the delivery of all emails from that sender.

This chart shows the increase in email volume specifically around Black Friday:

Chart methodology: Ometria September to December 2024 send volumes indexed against average pre-peak volumes. 

If you get blocked on Black Friday this will have a serious impact on your sales.

Build up your sending volume slowly and early

Black Friday is a prime period, and email volumes will skyrocket due to increased broadcast emails and automated email confirmations (AKA transactional sends). 

Sudden and large increases in email sends will raise suspicions and may result in some providers marking emails as spam.

This is why we recommend warming up your email lists with smaller batches to start with before gradually increasing the volume.

Be mindful that your contacts are going to be bombarded by nearly every brand they subscribe to at this time, so it's a balance between getting their attention and scaring them off.

Here are some things to consider to safely increase the email volumes: 

• How much will your daily send volumes increase by?
• How much does increasing your volumes affect deliverability and campaign performance?
  • Compare the previous occasions when sends have increased in volume to set benchmarks of what happens when you increase volumes by different amounts.
• What are you doing that will increase the volumes?
  • Will you be contacting older contacts who are not included in your day to day segments?
  • Or will you be increasing the frequency to existing contacts?

You should always ramp up your send volumes over the course of several sends. 

A good rule of thumb is to avoid sending more than double your average volume. 

Working backwards from your expected peak over Black Friday, you should look to slowly increase your send volumes so it doesn’t become such a notable spike, which could potentially trigger spam filters.

Mailbox providers will be more receptive to your messages because they’ve seen you send more volume over the last few weeks. 

Your Cyber Weekend volume won’t be a surprise, so they will be more likely to let the volume in.

We recommend:

• If you're increasing the frequency of your sends, slowly add in one extra campaign a week until you reach your desired sending frequency.
• If you're increasing the segment size of your audience, re-engage lapsed contacts first and slowly build up the volumes in the weeks prior to Black Friday. 

Re-engage your lapsed segments

On Black Friday it can be tempting to include unengaged contacts so that your emails reach a broader audience, in the hope that these subscribers are on the lookout for a good deal.

This approach can have a detrimental effect on getting emails into the inbox of even your most engaged contacts, and could harm your ability to deliver messages for several weeks or more. 

We recommend:

• Launching a specific re-engagement campaign around Black Friday.
• Only try re-engaging contacts who have previously engaged with your brand.
  • Contacts who have never opened or clicked an email, who have never registered a website visit and have never ordered are unlikely to be won back even at Black Friday. They are however likely to cause deliverability issues and should be excluded from campaigns. 

Target your lapsed audience using a broadcast campaign in early November, with content specifically instructing the subscriber to interact with the email to get Black Friday deals.

E.g., Use a personalised subject line:

Hey Paul, do you want to be first to hear about our Black Friday deals?

As open rates are no longer a reliable indicator of engagement, you should aim to include a strong call to action (CTA) encouraging recipients to click through instead, as clicks show a high level of contact engagement. 

Protect your most engaged subscribers

Your most engaged subscribers are key to your Black Friday success.

This customer segment will drive the most revenue for you, so making sure that they receive your campaigns is very important.

We recommend:

• Sending engaged subscribers your Black Friday campaigns first, then sending a separate campaign at least one hour later to those who are less engaged.
• Staggering your sends to less engaged contacts in batches of 20% of the segment size, and adding a wait of 30 minutes between each batch.

Use a snooze button

Not all subscribers want to take part in Black Friday and some can react negatively to seeing Black Friday campaigns. 

As a result, these contacts might mark emails as spam or unsubscribe from you. 

Rather than risk losing contacts, use a snooze button to allow them to opt-out of Black Friday communications allowing you to keep them subscribed in the long term.

We recommend:

• Using a snooze button.
• Speaking to your Customer Success Representative if you don’t already use a snooze button.

Send at the right time

Historical research has shown that opens and clicks on Black Friday spike at 10am and 4pm, however we have observed slight shifts in these times over recent Black Fridays. 

2024 trends

In 2024, Ometria saw clicks more spread out than previous years, with 24% of clicks occurring between 7:00am - 10:00am on Black Friday, with 7:00am - 8:00am being the busiest hour for sending.

We also saw a later peak between 4:00pm - 6:00pm, with 12.6% of clicks happening during these hours. 

These peaks are both significantly down on previous years with less of a lull in clicks taking place in between. 

Cyber Monday also saw a shift in click patterns with fewer clicks happening during the morning peak (6:00am - 9:00am), 19% in 2023 compared with 27% in 2023. 

As with Black Friday, click volumes then continued consistently through the day with a smaller evening peak occurring between 5:00pm - 7:00pm with 15% of clicks happening during this time. 

This shift suggests a change in behaviour with consumers either not being in as much of a hurry to read emails immediately, or being overwhelmed with the number they are receiving and taking longer to read some of them.  

As a result it is vital to make sure that you are top of the inbox when the subscriber is most likely to engage with your campaign.

We recommend:

• Sending your primary campaign between 6 and 10am to match the morning peak.
• Sending your secondary campaign between 12 and 4pm to cover lunchtime and be in the inbox for the evening peak

Get a head start on your competition

With so many retailers vying for their subscribers’ attention on Black Friday, starting the sales early ahead of the Black Friday weekend is a tactic we’ve seen increasing in the last couple of years.

In previous years some senders have started four to six weeks before Black Friday*, with some senders also now starting to reference Cyber Monday up to 8 weeks prior**.  

However starting too early can damage performance over Black Friday itself with early starters seeing engagement decline after 3 weeks of Black Friday sends***. 

We recommend:

• Taking a staggered approach to your sale, sending out new sale picks on a daily basis starting on Monday 17th November.

Start planning for post-Black Friday data clean up now

Getting through the Black Friday and Cyber Monday weekend without deliverability issues is always a fantastic achievement for any brand, however it can set you up for issues shortly after. 

The Christmas period and New Year often see an increase in deliverability issues such as rate limiting or blocklist.

These issues are caused by having collected high numbers of contacts who don’t engage once peak is over. 

Identifying and removing this data is key to maintaining good deliverability as you head into 2026. 

We recommend:

• Setting up a dynamic segment to track new subscribers gained between the start of your Black Friday offers and Christmas to help you understand how many contacts you have gained.
• Setting up a second segment for new subscribers who have been subscribed during your peak activity but have not yet opened an email - this allows you to track how many contacts are not engaging, so you can remove them after you have finished peak offers. 

How can we help you?

Your Customer Success Representative is here to help you. If you need assistance with putting any of this into practice, please get in touch.

If you're not using Ometria yet, then you can find out more about our platform and book a demo here.

Sources

*Source: https://www.mailcharts.com/blog/cyber-5-2020-email-insights 

** Source: https://www.sparkpost.com/blog/black-friday-cyber-monday-emails-in-2021/ 

***Source: https://www.sparkpost/.com/blog/flash-update-black-friday-cyber-monday