A broadcast to your whole list normally goes to everyone in one go: the people who read everything and the people who have not opened an email in a year. Sending in waves lets your engaged readers go first, so you see the result before deciding on the rest.
It protects your sender reputation too. Inbox providers watch how people react to your email, and a first wave of keen readers sends them the best possible signal.
Where to find it:
Emails, then Broadcasts, then + New Broadcast (or Edit on a draft), then step 4, Review & send, under Send in waves. Once sent, the waves are controlled from the broadcast's report.
The waves:
- Wave 1: Opened or clicked in the last 30 days.
- Wave 2: Opened or clicked 31 to 90 days ago.
- Wave 3: Not engaged in the last 90 days.
Each person's latest open or click decides their wave.
Turning it on:

- Build your email and audience as usual.
- On Review & send, under Send in waves, choose Send in waves, most engaged first instead of Send to everyone at once.
- Press Send Now, or schedule it as usual.
Wave 1 goes when the broadcast sends. If nobody in your audience is in wave 1, the first wave with people in it goes instead.
How many people are in each wave:

Your Audience step shows the split under the recipient count, for example 765 opened or clicked in the last 30 days, 119 in the 31 to 90 days before, and 276 not engaged in the last 90 days. When at least half of an audience of 50 or more has not opened or clicked in 90 days, a note suggests sending in waves.
Sending the next wave:

The broadcast report shows a 🌊 Sent in waves card with each wave, who is in it, its status (sent, next or waiting) and how many people it holds. Under the table you see how wave 1 did so far: delivered, opened and clicked, with the sales further down the report.
- Look at wave 1's results.
- Read the pace line, for example "Wave 2: 109 people. At about 3,000 an hour, that takes about 3 minutes."
- Optionally type a Speed in emails an hour for this wave and the rest of the broadcast. Leave it empty to keep the pace shown.
- Press Send the next wave, and confirm.
Send all remaining waves sends every wave that has not gone yet in one go, after you confirm. When everything has gone, the card says every wave has gone.
The safety rules:
- Each wave works out its audience again at the moment you send it, so new rules and new subscribers are taken into account.
- Nobody ever gets the email twice.
- Anyone who unsubscribed in between is not reached.
- Your Always leave out rules apply to every wave.
- Any hourly sending ceiling you set in Settings still applies to every wave.
The numbers for waiting waves are worked out when a wave goes, so the people count beside a waiting wave can be a little different by the time you send it. The exact figure is always used at the moment of sending.
Following it on the broadcasts list:

On Emails, then Broadcasts, a broadcast sent in waves shows where it has got to under its status, for example "wave 1 of 3 sent · next waiting", and "all 3 waves sent" when it is done.
A real example:
Leafwise Gardening sends "Tomato masterclass" in waves to its vegetable growers.
- Wave 1 goes on Wednesday morning to 575 people who opened or clicked in the last 30 days.
- By Thursday the report shows 40.3% opened and 15.3% clicked, with sales coming in.
- Anna presses Send the next wave and wave 2's 109 people get it at the usual speed.
- She decides to give wave 3, the 595 quiet readers, a different email instead, so she leaves it waiting.
When to use it:
Waves are ideal for a promotion to a big or older list. If wave 1 makes sales, send wave 2. If wave 1 goes quiet, you have protected your reputation with the people who were least likely to buy.
Tips:
- Give wave 1 a day before deciding. Most opens arrive in the first 24 hours.
- Write to the quiet wave differently. A short "still want these emails?" note often does better than the full promotion.
- Waves and drip speed work together: each wave goes at the broadcast's speed.
- To leave quiet readers out of every promotion, add an engagement rule to Always Leave People Out Of Broadcasts instead.