Reach personal inboxes
Improve reach across the personal inboxes customers use every day, with placement results for each provider.
Warm up your sender. Reach more inboxes.
Build sending history gradually and monitor where your email lands across Gmail, Outlook, and Yahoo. Available with Pro and Growth; sending usage is billed beyond your included credits.
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Reach customers across every major inbox.
Build sending history gradually and check placement across available Gmail, Outlook, Yahoo, and other provider samples as your schedule progresses.
Track inbox, Promotions, spam, and not-received results throughout the ramp to make informed decisions before increasing campaign volume.
Improve inbox placement
Reach business inboxes
Check available Microsoft 365 and Google Workspace samples before increasing business email volume.
Move further from spam
Compare inbox and spam results over time to see whether your sender is ready for more volume.
Build the reputation behind every campaign.
New and recovering senders need a record of consistent, successful delivery. MailSlurp creates that history before launches, promotions, lifecycle messages, and customer notifications depend on it.
Volume grows in measured steps while receipt, placement, and sender-health observations stay visible.
Build sender reputation
Grow without sudden spikes
Increase sending volume in steady steps that build trust instead of triggering the reputation damage caused by abrupt spikes.
Keep the sender healthy
Keep authentication, domain health, and blocklist signals in view while the sender builds a stronger delivery record.
Recover lost trust
Use a measured recovery schedule to observe an existing sender and decide when to increase volume.
Protect deliverability while volume grows.
MailSlurp uses controlled inbox receipts, delivery failures, domain health, Gmail Postmaster data, and placement tests to choose the next target. Strong signals keep the ramp moving; weaker signals slow it before customer reach drops.
Use each step to assess delivery before increasing volume. Placement also depends on your authentication, content, and recipient engagement.
Start adaptive warmup
Know exactly where mail lands
Measure inbox, Promotions, spam, and not-received outcomes instead of treating provider acceptance as the finish line.
Catch placement changes early
See when inbox reach changes during the ramp and adjust before important customer campaigns are affected.
Keep the team ahead
Bring placement changes into Slack or Microsoft Teams so the people protecting deliverability can act quickly.
Warm up every sender you already use.
Connect your provider through a supported native integration or authenticated SMTP, then warm up the mailbox, domain, and identity used for your customer email.
Use SendGrid, Resend, Amazon SES, Mailgun, Postmark, Gmail, Microsoft 365, Yahoo, Zoho, Fastmail, Brevo, Mailjet, and more.
Connect your provider
How email warmup works
Connect your sender, choose a measured schedule, and follow the results. These app screenshots use example data; placement varies by sender and provider.
01
Connect your sender
Choose your mail provider, verify the sending connection, and run a delivery test. An existing verified sender is ready to select.
02
Set a steady pace
Choose a new-sender or recovery plan, with a sending window and optional maintenance. This Gentle example targets 10 warmup messages a day over 28 days.
03
Follow the evidence
Review readiness and adaptive pacing alongside completed placement checks. Eligible plans add provider samples; compare their inbox and spam counts before the next increase.
Email warmup questions
Learn how gradual sending, provider samples, and ongoing monitoring work together.
How does MailSlurp email warmup improve deliverability?
MailSlurp increases sending volume gradually, confirms delivery to controlled inboxes, and uses available delivery and placement signals to adjust the pace. Review these observations alongside your authentication, message quality, and recipient engagement. Read the email warmup guide.
Will email warmup help more messages reach the inbox?
A gradual schedule helps you evaluate a sender before increasing volume. Mailbox providers decide placement using many signals, including reputation, authentication, content, and recipient engagement. Warmup does not guarantee inbox placement.
Which sending providers can I connect?
Use native connections for SendGrid, Resend, Mailgun, and Postmark, or authenticated SMTP for Amazon SES, Gmail, Google Workspace, Microsoft 365, Yahoo, Zoho, Fastmail, Brevo, Mailjet, and more. See provider setup details.
Which inbox providers can I track during warmup?
Track placement across Yahoo Mail, Gmail, Google Workspace, Outlook.com, Microsoft 365, Proton Mail, iCloud, and other major inbox providers. Compare inbox, Promotions, spam, and not-received results throughout the ramp.
Can I warm up a new sender and recover an existing sender?
Yes. Choose a gradual schedule for a new mailbox or domain, or use a recovery schedule to observe an existing sender at lower volumes before increasing traffic.
Can MailSlurp keep protecting deliverability after warmup?
Yes. Keep testing inbox placement, monitoring SPF, DKIM, DMARC, MX, and blocklists, and checking campaign content as real sending volume takes over. Explore deliverability monitoring.
Give every campaign a better chance to reach the inbox.
Warmup is available with Pro and Growth. Review included sender capacity and usage pricing, then choose a gradual schedule for your sender.
