Warmup AI Agent (WarmupHero)

How email warmup works?

When you connect a new (or cold) email account, WarmupHero starts by sending a small number of emails to verified inboxes. These emails get opened, replied to, and moved out of spam — all automatically. Over time, the volume increases as your sender reputation grows.

The result is that email providers like Gmail, Outlook, and Yahoo recognize your account as trustworthy, so your actual cold email campaigns see better inbox placement rates

Plan availability

WarmupHero is available across SmartReach.io plans. Check your current plan details in Settings → Billing to confirm warmup access and number of warm up account limits that may apply

How to activate warmup?

The setup steps depend on where your email accounts are hosted. Choose the path that matches your situation.

Path A

Mailboxes purchased through SmartReach If you bought your secondary domains and mailboxes from SmartReach (via Maildoso or Zapmail), you can activate warmup directly — no separate sign-up or API key needed. Here are the steps

• Click Settings from the left-side panel.
• Select Email Accounts from the settings menu.
• Find the email account you want to warm up from the list.
• Click the Activate Warmup button next to that email account. The warmup process begins automatically.

Path B

Below are the steps if your domains and mailboxes come from an external source (Google Workspace, third-party SMTP providers, etc.)

There are two ways to activate WarmupHero in SmartReach.io — from the Email warmup settings page, or directly from the Email accounts page.

Option A: From email warmup settings

1. Click Settings in the left sidebar.
2. Select Email warmup from the settings menu.
3. Click the Connect warmup button. Your WarmupHero account gets created automatically.

Option B: For specific email accounts

Then you can also do these steps to auto connect warm up hero for all your emails

Step 1: Open Settings

Step2: Go to Email Accounts

Step3: There you will find the option for Activate WarmupHeronext to the email account of choice* , just click on it. Your WarmupHero account will get auto created.

Connecting Gmail accounts for warmup

If you're connecting a Gmail account to WarmupHero, you'll need to use an app-specific password (not your regular Gmail password).

Note: Google requires app-specific passwords for third-party connections. You can generate one from your Google Account security settings under "2-Step Verification" → "App passwords." Watch this walkthrough video for a step-by-step guide on connecting Gmail accounts:

▶ Watch: How to connect Gmail to WarmupHero :

https://www.loom.com/share/5ed95ca73e82443c869816cfa44a4a01

Frequently asked questions

Do I need to create a separate WarmupHero account? No. When you click "Connect warm up" or "Activate WarmupHero" in SmartReach.io, your account gets created automatically. There's no separate sign-up.

Why do I need an app-specific password for Gmail? Google blocks sign-ins from third-party apps that use your regular password. An app-specific password lets WarmupHero connect securely without disabling your account's two-factor authentication.

Can I warm up multiple email accounts at once? Yes. Go to Settings → Email Accounts and click "Activate WarmupHero" next to each account you want to warm up.

How long does email warmup take? Most accounts need 2–4 weeks of consistent warmup before they're ready for full-volume cold email campaigns. The exact timeline depends on your account's current reputation and sending history.

Should I keep warmup running while sending cold email campaigns? Yes — keeping WarmupHero active alongside your outreach helps maintain your sender reputation, especially during high-volume sends.

Where can I find more help with WarmupHero? Visit the WarmupHero FAQ page for detailed answers on warmup settings, troubleshooting, and best practices.