Piotr Mikrut’s Experiment5M Scaled Cold Outreach and Grew 800% with Smartlead

Key Highlights

• Grew his cold email business 800% and 50k MRR in a year.
• 4 hours to 5 minutes time reduction in mailbox connection.
• Campaign data import time reduced by 1-2 hours.
• Client responsiveness improved via direct email access.

Company Overview

Piotr Mikrut is the founder of Experiment5M, a customer acquisition agency specializing in cold outreach through email, LinkedIn, and personal branding. Serving B2B clients including marketing agencies, software companies, and SaaS businesses primarily across Europe and the US, Experiment 5M delivers personalized contact databases, strategic outreach, and full campaign management.

Piotr’s cold email journey started as a cost-effective growth channel when launching Greencrm, a solar industry-focused CRM company. He quickly realized the power of cold outreach and transitioned into agency work, helping clients generate substantial growth via outbound email.

The Challenge

Initially, Piotr used various outreach tools but faced major hurdles:

Manual Processes

Connecting large numbers of mailboxes and managing multi-campaign data transfers were time-consuming and error-prone.

Deliverability Risks

Managing bounced contacts and do-not-contact lists was difficult, causing frustration when contacts received unwanted follow-ups.

Limited Automation

Lack of strong API integrations restricted campaign automation, leading to inefficient workflows.

Client Communication

Clients struggled to view and respond to campaign replies efficiently without direct access to platforms.

Piotr needed a scalable, reliable solution with powerful automation and deliverability features to support his growing client base.

Why Smartlead?

After researching and testing a few platforms in the cold email domain, Piotr chose Smartlead for its unique strengths:

Robust API

Enabled seamless automation by integrating campaign launches and response handling directly with Clay and other tools.

Bulk Mailbox Connection

Allowed connecting hundreds of mailboxes quickly, reducing campaign setup time from hours to minutes. Also, the master inbox is a quick and efficient way to manage all replies in a single place.

Shared Client Access

Provided client portals where clients could securely log in and engage with their campaign data.

Preview & Spintax Tools

Offered clear previews of spintax variations, ensuring high-quality, unique messaging.

Direct Email Access

Enabled replies directly from the sending email account within Smartlead, improving client responsiveness.

Deliverability Focus

Comprehensive inbox warm-up and spam protection tools kept campaigns healthy.

Piotr appreciates that Smartlead is widely adopted in his professional community, enhancing collaboration and support.

Our Solution: Streamlining with Smartlead Automation and Integration

Experiment5M integrated Smartlead tightly into their outbound strategy:

• Automated campaign creation, lead enrichment, and segmentation through API integration with Clay.
• Leveraged Smartlead’s spintax and preview features to optimize email uniqueness and quality.
• Managed mailbox pools efficiently by bulk connecting and rotating sending accounts.
• Used Smartlead’s client portal for transparent reporting and easy client engagement.
• Automated reply categorization and forwarded responses into project management tools like ClickUp.

Results Achieved

• Grew his cold email business 800% and 50k MRR in a year.
• Mailbox connection time reduced from 4 hours to 5 minutes.
• Campaign data import time reduced by 1-2 hours.
• Client responsiveness improved via direct email access.
• Reply rates consistently grew high, driving engagement.

Notably, the automation and bulk mailbox connection saved the team countless hours monthly, allowing more focus on campaign strategy and client success.

Challenges & Areas for Improvement

Piotr shared some things he would like to see from Smartlead in the future:

• A more flexible freemium pricing model based on domain and contact database size to better scale with agency growth.

Piotr believes Smartlead’s rapid feature development and open feedback culture help mitigate issues over time.

Final Thoughts

Piotr Mikrut’s experience with Smartlead highlights the power of automation and deliverability-centric platforms in scaling cold outreach agencies. By integrating Smartlead’s API-driven tools and client portals, Experiment5M has streamlined campaign management, improved client transparency, and significantly cut manual workload.

“Smartlead’s automation and deliverability features transformed how we run outbound campaigns. The API integrations and client portals gave us the scalability and transparency we needed. While there’s room for growth, this platform has been a game changer for our agency.” – Piotr Mikrut, Founder, Experiment5M

This case study demonstrates how a robust email outreach platform can empower agencies to automate at scale, drive engagement, and build trusted client relationships — all critical factors for success in today’s competitive cold email landscape.