Reply.io vs Warmup Inbox: Cold Email Platform vs Email Warmup Tool Comparison
Compare Reply.io (cold email platform) and Warmup Inbox (email warmup tool) side by side. See pricing, features, and integrations to decide which one, or both, your stack needs.
Reply.io is a cold email platform built for outreach, sequences, and pipeline generation, priced from $59/mo, while Warmup Inbox is a dedicated email warmup tool that builds sender reputation across more than 30,000 real inboxes, priced from $19/mo. They serve different core jobs, so many teams run both together.
Key takeaways
- Reply.io's entry plan is $59/mo for the Email Volume tier with 1,000 active contacts and unlimited emails.
- Warmup Inbox's entry plan is $19/mo for the Basic tier offering 75 warmup messages per day.
- Warmup Inbox exchanges natural-looking email with a network of more than 30,000 real inboxes to build sender reputation.
- Reply.io integrates with HubSpot, Salesforce, Pipedrive, Copper CRM, Zendesk Sell, Close, Zapier, Make, and n8n.
- Warmup Inbox integrates with Gmail and Workspace, Outlook and Microsoft 365, Zoho Mail, Amazon SES, Mailgun, SendGrid, and Sendinblue (Brevo).
Reviewed and updated September 2, 2026
Reply.io vs Warmup Inbox: Cold Email Platform vs Email Warmup Tool Comparison
Reply.io (cold email platform) and Warmup Inbox (email warmup tool) sit next to each other in many outbound stacks. They are not substitutes for each other on every job, so this comparison covers pricing, features, and integrations for each and points out where the two meet.
The Quick Answer
Reply.io is a cold email platform for cold email outreach; Warmup Inbox is an email warmup tool for email domain warming and deliverability. By each vendor's own wording, Reply.io lists unlimited email warmup and 1 billion b2b contacts database, and Warmup Inbox lists email warmup and cold email sequence.
Warmup Inbox offers a lower entry point at $19/mo compared to Reply.io at $59/mo.
If your priority is sending campaigns that land in the inbox and generate replies, Reply.io is the one built for it; for building sender reputation and improving inbox placement, that is Warmup Inbox. Many teams run one of each.
Understanding the Core Difference
Reply.io is AI-powered sales engagement platform with 1B+ B2B contacts, multichannel sequences, and AI SDR capabilities.
Warmup Inbox is Email warmup service that exchanges natural-looking email with a network of more than 30,000 real inboxes to build sender reputation automatically. Also offers cold email sequences, language warmup, ESP warmup and IP warmup from the same dashboard.
The two platforms take different approaches to solving the same core challenge.
Pricing Comparison
Email Volume
Basic
Reply.io Pricing (as of September 2026)
| Plan | Price | Contacts | Emails |
|---|---|---|---|
| Email Volume | $59/mo | 1,000 active contacts | Unlimited |
| Multichannel | $99/mo | Unlimited active contacts | Unlimited emails; 10 mailboxes |
| Agency Core | $210/mo | Unlimited clients & users | Unlimited mailboxes |
| AI SDR Starter | $800/mo | 1,000 active contacts | Unlimited mailboxes & warm-ups |
Source: Reply.io Pricing
Warmup Inbox Pricing (as of September 2026)
| Plan | Price | Contacts | Emails |
|---|---|---|---|
| Basic | $19/mo | per inbox | 75 warmup messages/day |
| Pro | $59/mo | per inbox | 250 warmup messages/day |
| Max | $99/mo | per inbox | 1,000 warmup messages/day |
| For agencies & teams | Contact Sales | Custom plans starting at 15 inboxes | custom |
Source: Warmup Inbox Pricing
Pricing Analysis
Warmup Inbox offers the lower entry point ($19/mo vs $59/mo). Teams watching their budget will appreciate the savings, especially when starting out.
Features Breakdown
- Unlimited email warmup
- 1 billion B2B contacts database
- Anti-spam & deliverability suite
- LinkedIn automation (add-on)
- SMS and calls (add-on)
- AI personalization
- and 3 more listed below
- Email warmup
- Cold email sequence
- Language warmup
- ESP warmup tool
- IP warmup
- Spam & Category monitoring
- and 3 more listed below
Reply.io Key Features
- Unlimited email warmup
- 1 billion B2B contacts database
- Anti-spam & deliverability suite
- LinkedIn automation (add-on)
- SMS and calls (add-on)
- AI personalization
- AI SDR capabilities
- Multi-workspace for agencies
- 14-day free trial
Warmup Inbox Key Features
- Email warmup
- Cold email sequence
- Language warmup
- ESP warmup tool
- IP warmup
- Spam & Category monitoring
- Email reputation Check
- Human-like AI generated content
- Developers API
The two lists below are a diff of each vendor's own feature list by exact wording, so a capability both tools offer can appear on either side under a different name.
Listed only by Reply.io
- Unlimited email warmup
- 1 billion B2B contacts database
- Anti-spam & deliverability suite
- LinkedIn automation (add-on)
- SMS and calls (add-on)
- AI personalization
- AI SDR capabilities
- Multi-workspace for agencies
- 14-day free trial
Listed only by Warmup Inbox
- Email warmup
- Cold email sequence
- Language warmup
- ESP warmup tool
- IP warmup
- Spam & Category monitoring
- Email reputation Check
- Human-like AI generated content
- Developers API
Integration Ecosystem
Reply.io Integrations
Reply.io connects with: HubSpot, Salesforce, Pipedrive, Copper CRM, Zendesk Sell, Close, Zapier, Make, n8n.
Warmup Inbox Integrations
Warmup Inbox connects with: Gmail & Workspace, Outlook & Microsoft 365, Zoho Mail, Amazon SES, Mailgun, SendGrid, Sendinblue (Brevo), Any inbox with SMTP.
Integrations listed only by Reply.io: HubSpot, Salesforce, Pipedrive, Copper CRM, Zendesk Sell, Close, Zapier, Make, n8n.
Integrations listed only by Warmup Inbox: Gmail & Workspace, Outlook & Microsoft 365, Zoho Mail, Amazon SES, Mailgun, SendGrid, Sendinblue (Brevo), Any inbox with SMTP.
Use Case Recommendations
Best Fit for Reply.io
- Organizations with complex tech stacks needing broad integration support (9 integrations)
- Sales teams running high-volume outbound email campaigns
- Agencies managing multiple client outreach programs
- SDR teams focused on pipeline generation
Best Fit for Warmup Inbox
- Budget-conscious teams looking for an affordable email warmup tool
- Enterprise buyers who prefer custom pricing and dedicated support
- Teams launching new email domains for outreach
- Organizations recovering from deliverability issues
Feature Comparison Summary
| Feature | Reply.io | Warmup Inbox |
|---|---|---|
| Starting Price | $59/mo | $19/mo |
| Top Tier Price | $800/mo | Contact Sales |
| Total Features Listed | 9 | 9 |
| Integrations | 9 | 8 |
Getting Started Checklist
- Define your cold email outreach and email domain warming and deliverability requirements and monthly budget
- Estimate your expected email sending volume and warmup email volume to find the right tier
- List the integrations your team currently relies on
- Sign up for free trials or demos of both platforms
- Run a small test with each tool before making a commitment
- Evaluate the onboarding experience and support quality
Final Thoughts
Reply.io serves the cold email outreach side of an outbound stack and Warmup Inbox the email domain warming and deliverability side. Warmup Inbox offers a more accessible entry point at $19/mo, while Reply.io starts at $59/mo. Your decision should weigh pricing against the specific features that matter most for your workflow.
Start with a trial of each to see which platform fits your team's daily process. The best tool is the one your team actually uses consistently.
Pricing and features verified as of September 2026. Visit Reply.io and Warmup Inbox for current information.
Frequently asked questions.
Frequently asked questions- What is the main difference between Reply.io and Warmup Inbox?
- Reply.io is a cold email platform for sending outreach campaigns and generating replies, while Warmup Inbox is an email warmup tool focused on building sender reputation and improving inbox placement. They solve different core problems, though many teams use both in the same stack.
- Which is cheaper, Reply.io or Warmup Inbox?
- Warmup Inbox has the lower entry price at $19/mo for its Basic plan, compared to Reply.io's $59/mo Email Volume plan. Budget-conscious teams starting out may prefer Warmup Inbox's lower cost of entry.
- Does Reply.io include email warmup features?
- Yes, Reply.io lists unlimited email warmup as one of its own features alongside its cold outreach tools. However, Warmup Inbox is built specifically around warmup, offering language warmup, ESP warmup, and IP warmup from a dedicated dashboard.
- Can Reply.io and Warmup Inbox be used together?
- Yes, the article notes that many teams run one of each since the tools serve different jobs. Reply.io handles cold email sequences and outreach while Warmup Inbox focuses on building and maintaining sender reputation.
- What integrations does each tool support?
- Reply.io integrates with HubSpot, Salesforce, Pipedrive, Copper CRM, Zendesk Sell, Close, Zapier, Make, and n8n. Warmup Inbox integrates with Gmail and Workspace, Outlook and Microsoft 365, Zoho Mail, Amazon SES, Mailgun, SendGrid, and Sendinblue (Brevo).
About the author.
Tim Carden is CMO / CTO at RevenueFlow, which builds and operates outbound revenue engines for B2B companies. Studied at McGill University.
Tim Carden · CMO / CTO
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