Warm up your inboxes. Scale your cold outreach safely.
Build bulletproof sender reputation on Gmail, Google Workspace, and SMTP accounts with our decentralized peer-to-peer warm-up network.
How automated warm-up works
Get your sender accounts fully ramped and protected in 4 automated steps.
1-Click Activation & Duration Choice
Select your sender account, choose your target duration (7, 14, or 21 days), and join the OutSends P2P pool with zero complex configuration.
Decentralized Peer-to-Peer Exchanges
Your sender exchanges natural business emails with other active network inboxes across different providers, avoiding single-destination spam flags.
Contextual Thread Replies
Our engine simulates realistic human interactions by sending replies with RFC-compliant In-Reply-To and Google threadId headers.
Automatic Graduation to "Ready"
Accounts are safely protected from campaigns while warming up, then automatically unlock for outreach when reaching 95%+ deliverability health.
Why choose OutSends for email warm-up
Built natively into your outreach platform without third-party subscriptions.
- Decentralized P2P Pool: Avoid burned seed inboxes by exchanging emails across hundreds of real, active user accounts.
- Authentic Email Threading: Google and Outlook see genuine two-way conversations with native threadId integration.
- Automatic Campaign Protection: Accounts are locked from campaigns during ramp-up to eliminate the risk of premature sending.
- Zero Hidden Costs: Included directly inside your OutSends subscription with generous account quotas (up to 50 concurrent senders).
- 1-Click Inbox Protection: Set a single email filter matching
outsends-warmupto keep test threads cleanly out of your primary inbox.
Frequently asked questions
Everything you need to know about OutSends warm-up.
How long should I warm up a new email account?
We recommend 14 days for any new domain or newly created sender mailbox. For mature accounts needing a quick boost, 7 days is usually sufficient. For domains recovering from spam penalties, choose 21 days.
Will warm-up emails clutter my personal inbox?
No. We provide a 1-click filter rule for Gmail and Outlook that automatically marks incoming test replies as read and archives them, keeping your daily inbox 100% clean.
How many senders can I warm up at the same time?
Starter includes 3 concurrent warmup senders, Pro includes 10, Growth includes 20, and Team includes 50 concurrent senders.
Can I send campaigns while warm-up is active?
To protect your domain from burning, senders are dedicated to warm-up during their ramp-up cycle. Once completed, they automatically unlock and can be selected for high-volume outreach.
Ready for 100% primary inbox delivery?
Start your 14-day free trial today. Warm up your inboxes and launch high-converting outreach.