Determining the best time or the best day to send your email marketing campaign is an essential piece of your overall email marketing strategy. And for good reason. High-quality content timed to arrive in your recipient’s inbox at the right time can help increase both your engagement and delivery rates.

Although there’s no magic answer to when you should send your email campaigns, there’s a lot in your control to test and find your email send time “sweet spot.”

Whether you use automation or not (we provide tactics for both scenarios below), there is a method that will help you achieve optimal send times. The tips and insights below can help you get started and help you dial-in your send time so your email campaigns have the highest chance of being read.

Getting started: benchmarks and data to keep in mind

Wondering where to start? Consider looking at historical data around send times and correlating engagement rates. We pull send data from our senders over holiday time periods here at Twilio SendGrid, and we’ve found that during Black Friday and Cyber Monday of 2018, the peak send time across senders was 7 AM and that peak opens occurred between 8 AM and 9 AM MDT.

And most recently, over the 2019 Memorial Day weekend, we saw that the peak send time was also 7 AM. But when it came down to analyzing the most common open times, results varied so much that our data scientists couldn’t find a statistically significant time that people were most likely to open an email.

Outside of specific holiday sending and open data, HubSpot as also found that:

  • Sending on a Tuesday vs. other weekdays generally correlates with slightly higher open rates.
  • An 11 AM (EST) send time results in higher open rates.
  • Open rates tend to drop off later in the week and through the weekend.

So as you can see, not all the datasets will always agree with each other all of the time. Starting with a Tuesday send time at either 7 AM or 11 AM will be solid places to start and use as a control in your email send testing. Again, the best way to determine your optimal send time is to test (and keep testing) variables until you find enough statistical significance to conclude that one time is better than another.

Keep in mind all the other variables in place that determine optimal email send times.

For example, those who are in the market to purchase software are probably very unlikely to want to purchase or engage with you over the weekend because they aren’t at work.

But if you email on behalf of a B2C brand, the weekend sends might be some of your highest-converting and engaging campaigns. I know for a fact that the majority of my online shopping occurs on Saturday morning on the couch over coffee, and I’m often digging through my inbox to find that promotion that I’m looking to use.

Here at Twilio SendGrid, I work on our monthly blog digest (psst: you can sign up for that here) and I’m constantly tweaking the send time but have generally landed on sending the campaign out on either Tuesday or Wednesday between 10 and 11 MST.

If you would like to dive deeper into industry email engagement benchmarks, be sure to download our 2018 Email Benchmark Report so that you can compare your engagement rates with other brands within your industry and even your region.

What should I be testing?

To start simple, include a control send time and a variable send time to A/B test your send time. In Twilio SendGrid’s Marketing Campaigns, you can set this up to automatically switch to the winning version after a set amount of time or variance has been reached. For a deeper dive into A/B testing, check out Twilio SendGrid’s email A/B best practice guide.

Here are some ideas of what variables you could decide to test first to see what is resonating best:

  • Time of day – day vs. evening
  • Day of send – week vs. weekend
  • Specific time blocks or periods – start of workday vs. end of workday vs. lunch

Once you’ve determined what day and what time of day is working best for you, you can make granular tweaks to try and be the top email in your recipient’s inbox.

When to NOT send

Avoid sending at the very top of the hour or 15, 30, or 45 minutes past the hour. Why? Most marketers use these times to send their email campaigns because they come to mind first.

This practice causes a backup at the ISPs which can cause your emails to be deferred. Instead schedule your 11 am emails for 10:55 instead (and don’t forget to observe and record the results!)

Some ISPs have told SendGrid delivery consultants directly that the ideal time for marketers to send their campaigns is during non-peak times like 7, 21, or 36 minutes past the hour. Sending at these non-peak times will increase how fast your messages are delivered.

Send time strategy: following the sun

What if your email recipients live around the world and you don’t have the capabilities or resources to segment out your email list for each time zone to receive their email at the right time? Consider following the sun.

Follow the sun campaigns are typically sent to recipients at or around the time that the sun is rising in their geographic location.

Following the sun gives you a higher probability that your message will be at the top of recipients’ inboxes. This will also reduce the burden on the ISP because the campaign will be split into 38 smaller sends based on time zones (if you have a global audience across all time zones).

Depending on the capabilities of your ESP, you will need to figure out how to tactically send to your audience at the optimal time. Before you can implement this strategy, you will need to know the general geographic location of your recipient.

When it comes to transactional email, which is typically triggered by an action the recipient has taken, send time can be less critical. This is because transactional email is not sent in bulk to hundreds of thousands of recipients at once, it happens organically. Read more about the differences between marketing and transactional email.


Finding the best time to send your email is going to help improve your engagement and conversion rates. Always keep in mind the following when determining when to send your email campaigns:

  • Start by looking at performance data benchmarks
  • Consider the type of email you are sending and the capabilities of your ESP
  • Send at “odd” times instead of at the top or bottom of the hour
  • Test, test, test!

Remember that email send time is only a piece of your email marketing program. And no matter how optimized your email send time is, if you aren’t providing engaging and valuable content, you won’t persuade users to keep opening and engaging with your emails.

Email send time is a bit of a mix between art and science so don’t be afraid to try new things either! For even more information on optimizing your email program head on over to Twilio SendGrid’s Email Marketing Best Practices for 2019.

As a senior content marketing manager at SendGrid, Kelsey oversees the SendGrid Delivery blog. Her downtime is dominated by either her mountain bike or skis (depending on current weather forecast)–and mixing up a salty marg afterward.