The Unified Inbox for Instantly
Every reply from your Instantly campaigns lands in one Unified Inbox. AI inbox agents read each one, respond from the same sender in under 5 minutes, follow up automatically, and book meetings on your calendar.
How the Underfive Unified Inbox Works with Instantly
Connect via Webhook
Add Underfive's webhook URL to your Instantly account. When a lead replies to your campaign, Instantly sends the message to your Unified Inbox instantly.
Inbox Agents Read and Respond
An inbox agent reads the lead's message, understands the context, and generates a human-like response. It handles questions, objections, and scheduling requests.
Response Sent via Instantly
The inbox agent sends the response back through Instantly from the same sender. The email appears in the same thread. The conversation continues seamlessly.
Meetings Booked Automatically
When a lead is ready to meet, your inbox agents negotiate times and book the meeting on your calendar. You receive the invite with all details.
Why Use a Unified Inbox with Instantly
Respond in Under 5 Minutes
Every Instantly reply gets a response in under 5 minutes. Fast responses dramatically increase meeting rates.
Human-Like Responses
Inbox agents write responses that sound like a real person. Leads engage naturally.
Handles Full Conversations
Your inbox agents manage the entire conversation from first reply to booked meeting.
Books Meetings
Meetings are scheduled automatically on your calendar. No manual coordination required.
Underfive Works With Instantly, Not Instead of It
Instantly is a cold email platform. Underfive is the Unified Inbox where the replies land. They work together. Instantly sends campaigns. Underfive's inbox agents handle the replies. You keep using Instantly exactly as you do today.
Add a Unified Inbox to Your Instantly Campaigns
Start with 50 free replies. Connect Instantly in under 5 minutes.
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