Why Cold Email Pros Are Using Multiple ESPs

Why Use Multiple ESPs for Cold Outreach?

Relying on a single ESP to power your cold outreach is an unnecessary risk. Deliverability can tank without warning, domains get flagged, IPs get throttled. Just one outage or dip in reputation, and your entire outbound stalls.

The solution is straightforward: run a multi-ESP infrastructure. It’s how the top outbound teams scale safely and keep inboxing consistent.

But before we talk more about multi ESPs, ask yourself this:
Do you have leads to continuously keep your campaigns running?

Most cold outreach campaigns eventually run into the same issue - not enough leads.

This is why you need a constantly supply of leads, to keep your campaigns fueled and your outreach going. This is why our CEO Frank and Isabella Lee will show you how to keep your campaigns fueled, and your pipeline warm!

So, Join Frank and Isabella as they break down exactly how to build a predictable Lead Gen pipeline!

With your leads pumping, you also of course need to act on them, which is where multi-ESPs come in.

What Is a Multi-ESP Setup?

A multi-ESP approach to cold emailing means that you distribute your mailboxes across multiple email providers. Instead of the traditional approach where sales teams use one mailbox provider, your campaigns are spread across several infrastructure providers which provides benefits such as:

1. Minimize Risk Per provider
By diversifying your infrastructure, you isolate potential issues. A flagged domain or ESP doesn’t shut down your entire pipeline and keeps a stable outreach.

2. Smart ESP usage
Each ESP has its edge. Some inbox better with Gmail, others have better IP pools or stronger automation. With a multi-ESP setup, you can assign each platform to the job it does best and take advantage of each tool.

3. Matching Your Prospect’s ESP
Deliverability improves when your message comes from the same provider your prospect uses. Gmail to Gmail, Outlook to Outlook. Matching your ESP to your recipient’s improves trust signals and inbox placement. A multi-ESP setup lets you route messages through the best sender for each domain type.

In essence, if you’re running cold email in 2025 you need diversified infrastructure that can handle the real work.

• Primeforge for your premium campaigns to other Google and Outlook users,

• Mailforge for when you start out and want a quick and easy setup,

• Infraforge for domain control and advanced setups.prime forge

Together, they keep your cold email safe, stable, and scalable.