Email warmup

What you can do with Email warmup

# Open Email warmup

1. Find your servers and their warmup state

   In the left sidebar, under Sending, click Email warmup (1). At the top you see how many servers are Warming up, Completed and Not warming, and how many emails were Sent today.

   The table lists every sending server:

   • Warmup progress: the plan day the server is on, for example Day 13 of 30.
   • Today: emails sent today against today's allowance, for example 183 / 268.
   • Last 14 days: a small chart of recent sending.

   Under the server name a label shows the state: Warming up, Not warming, Paused, Complete, Starts (date) for a warmup scheduled to start later, or On hold after a safety stop.

   A server with no warmup has a Set up warmup button (2). The others have Manage.

   

# Start warming up a server

1. Choose a warmup plan

   Click Set up warmup next to the server. At the top (1) choose:

   • Use a recommended plan: pick a ready-made plan. Plans published by your provider and plans you have built yourself (marked Your plans) are listed here.
   • Build my own: set your own day-1 volume, growth and safety rules for this server.

   Then click a plan card (2). Each card shows the start and peak volume (for example 50 → 2,879/day), roughly how many days the warmup takes, and its Risk: Low, Medium or High.

   

2. Pick the start date and start

   Start date (1) is day 1 of the plan. Leave it on today to start now, or pick a later date to schedule the warmup. Nothing is sent from the server before the start date.

   Click Start warmup (2). From now on every campaign and automation that sends through this server follows the plan's daily allowance.

   

3. Check the plan preview

   Before you start, the Plan preview on the right shows exactly what the plan will do:

   • Day 1 volume, the growth (Added each day or Growth multiplier), when it finishes and Full warmup takes.
   • Schedule: every day with its date and allowance, and the date the warmup Finishes. Click Show all to see every day.
   • Further down: Milestones and a chart of the daily allowance from day 1 to full volume.

   The dates already leave out weekends when the plan does not send on weekends.

   

# Build your own warmup plan

1. Open Warmup plans

   On the Email warmup page click Warmup plans. Each plan shows how its volume grows, the servers it is Applied to and its Risk. Use the menu (⋮) on a plan to Edit it, Apply to a server, Duplicate it or Delete it.

   Click New plan.

   

2. Set the volume

   Give the plan a Plan name and choose How volume grows:

   • Linear adds the same number of emails every day (for example 20, 35, 50, 65…).
   • Exponential multiplies the previous day by the Growth multiplier. It grows slowly at first and much faster later.

   Under Volume plan set:

   1. Emails on day 1: the allowance on the first day.
   2. Added each day (or Growth multiplier): how fast it grows.
   3. Finish when: the warmup ends when the daily volume reaches Stop at daily volume, after a number of days (Stop after days), or after a total number of emails (Stop after total emails).
   4. Also send on weekends: when this is off, Saturdays and Sundays send nothing and do not count as plan days.

   Full warmup takes updates as you type.

   

3. Set the safety rules and save

   With Enable safety checks and Pause on negative signals switched on, warmup protects your reputation by itself. Set the limits:

   1. Max bounce rate (%): the share of hard bounces you accept.
   2. Max complaint rate (%): the share of recipients who mark your email as spam.

   The rates are checked every 30 minutes over the last 7 days, once enough emails have been sent to judge. If one goes above its limit, sending from the server is put on hold until you resume it (see When sending is on hold below).

   Click Save plan.

   

# Follow the progress

1. Read the summary

   The top of the page shows:

   • Warmup progress: today's plan day out of the total, and the start date.
   • Today: emails sent today against today's allowance, with a bar.
   • Sent during warmup: the total so far, and how many failed.
   • Next sending day with its allowance, the date the plan Finishes, and whether it Sends on weekends or has Weekends off.

   The buttons below are for changing the warmup: Pause warmup, Change plan, Manage, Reset warmup and Remove plan. They are explained in the next section.

   

2. Watch the sending health

   Sending health shows the Hard bounce rate and Complaint rate of this server over the last 7 days, next to the limits from the plan (for example 0.46% / 4%). Safety checks on means the server is put on hold automatically if a rate goes over its limit.

   The rates are only judged after enough emails have been sent, so a new server shows 0% at first.

   

3. Compare allowance and real sends

   The chart Allowance vs. actual sends draws the plan's Daily allowance as a dashed line for every day, and what was Actually sent as a solid line up to Today.

   If the solid line stays far below the dashed line, you are sending less than the plan allows. That is fine, but the plan still moves on one day at a time, so the server builds less reputation than planned.

   

4. See every day

   Below the chart, Full schedule lists every plan day with its Date, Allowance, Sent and Status: Done, Today, Upcoming, Skipped or Adjusted. Day by day shows only the days that already sent, including failed sends.

   The menu (⋮) on today or a future day lets you change that day's volume or skip that date.

   

# Change a running warmup

1. Use the Manage menu

   Click Manage on the server's warmup page:

   • Jump to day…: make today a later plan day if the server is healthy and you want to go faster, or an earlier day to slow down. Past history is kept.
   • Change a day's volume…: replace the planned allowance for one future day only.
   • Skip a date…: nothing is sent that day, and the plan continues the next day.
   • Change start date… (only before a scheduled warmup has started).
   • Export CSV: download the full schedule.

   The other buttons:

   • Pause warmup stops limiting the server: it keeps its plan and progress but sends without warmup limits until you click Resume.
   • Change plan switches to another plan and restarts at day 1.
   • Reset warmup deletes all progress and restarts at day 1.
   • Remove plan ends warmup; the server then sends without limits.

   

2. A warmup scheduled for later

   A server whose start date is in the future shows Upcoming, a Starts (date) label in the list, and its first sending day under Next sending day. Nothing is sent from it until then.

   With Weekends off, a warmup started on Saturday or Sunday begins on Monday.

   

# When a campaign is on hold

1. See why a campaign waits

   Click the orange Sending - On hold label in the campaign list or on the campaign's report. The window tells you why it waits and when sending resumes:

   • Today's limit has been reached: the warmup allowance for today is used up.
   • Weekends: the plan does not send on Saturdays and Sundays; sending continues on the next weekday.
   • Start date not reached yet: the warmup on the server has not started.
   • Skipped day: today is skipped in the server's plan.

   In all of these cases you do not need to do anything. The campaign is still sending, the remaining emails wait in the queue, and they go out automatically on the next sending day.

   

2. Resume after a safety hold

   If too many emails bounced or were marked as spam, the server's warmup page shows Sending is on hold and the server is labelled On hold in the list. Sending from this server stays stopped until you resume it. It does not resume by itself.

   1. Fix the cause first. For bounces, remove invalid, old or inactive addresses (verify the list). For complaints, check who you send to and what you send.
   2. Click Resume.

   

# Send one campaign through several mailboxes

1. Give each mailbox its own address

   Most mailboxes only send from their own address. Gmail, Outlook and most SMTP accounts reject or rewrite any other From address.

   For each mailbox, open Sending servers, click the server and fill in Default from email with the mailbox's own address. Then set up warmup for each mailbox as described above.

   

2. Choose the mailboxes in the campaign

   In the campaign's Setup step, find Sending servers:

   1. Switch off Use all servers randomly, then switch on each mailbox the campaign should use. Every email is sent by one of them, picked at random; Adjust weights lets one mailbox take a bigger share.
   2. Switch on Each mailbox sends from its own address. Every email then goes out from the address of the mailbox that sends it, shown as Sends as … under each mailbox. The From email field is hidden because it is not used.

   Leave Reply-to email empty to get each reply in the mailbox that sent the email, or fill it in to collect every reply in one inbox.

   Click Save & Continue.

   

Common questions

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