}

Ever wonder what happens if you combine two cold email masterminds who believe in zero capital, zero marketing spend, and purely outbound hustle? You get Letstrike—an agency that’s grown to 500+ clients purely by harnessing the power of advanced cold email strategies. Its co-founders, Charles Moriceau (COO) and Max Moriceau (CEO), share the same last name (and a lot of the same drive). They carved out a reputation for producing insane numbers of sales meetings for B2B companies. Their tagline, “get leads straight in your inbox,” pretty much sums up what they do.
But how do you keep scaling an agency that juggles multiple subdomains, multiple languages, and multiple clients in one place—without your domain (or your brain) going up in flames? Let’s just say the duo found the answer in Smartlead, a tool that helped them unify their approach, maintain top-notch deliverability, and avoid the dreaded spam folder. And they’re here to share how it all went down.
Let’s rewind a bit. Charles had been in the cold emailing space for about a decade, first experimenting when he ran a video production company and quickly grew it to 50 employees. He realized that once you crack cold outreach, you can do wonders—like fueling a full-blown pipeline with minimal ad spend. Meanwhile, Max had a background in software sales, wearing hats like Country Manager in Australia for a software integration partner. Both recognized that outbound works—if you do it right.
So they decided to form Letstrike roughly six years ago, with the dream of building a “done-for-you cold emailing solution” that B2B businesses could rely on to scale. Early on, they discovered they had a knack for not only booking a few calls here and there, but for delivering real volumes of qualified leads. By leaning on purely outbound channels, they soared to 500+ clients over the years. Not too shabby for a duo that never spent a dime on marketing, right?
Max’s summary: “We’ve grown on zero capital, zero marketing, purely cold emailing—and that’s the story we love to tell.” Indeed, for them, it’s a badge of honor that they built something that soared without big marketing budgets.
As Letstrike grew, so did the complexity of managing all these client campaigns. Imagine you have 100 or more active clients:
How do you keep track of all these inboxes, ensures deliverability, and rotate addresses so none get hammered? Charles recalls that in the old days, they tried “Yet Another Mail Merge,” or other simpler solutions. But that quickly became a headache: no advanced domain warm-up, no fail-safe for domain meltdown, no sophisticated analytics beyond basic open/click rates.
Meanwhile: Deliverability was becoming a real challenge in the 2020s. Gmail and Microsoft Outlook had ramped up spam detection, so if you tried “spray-and-pray,” you were toast. Letstrike needed a platform that was:

At some point, the duo came across Smartlead (they mention hearing about it in various cold emailing circles). The big draw? They needed a tool that was basically “one dashboard to rule them all,” especially for an agency model. Charles and Max put it this way: “If you try to manage 100 separate seats with a smaller tool, you spend all day in admin chaos. Smartlead let us unify them.”
What stood out:
And so, Letstrike jumped in with both feet, migrating a chunk of their campaigns to Smartlead. The result: they found it simpler to handle day-to-day domain checks, deliverability audits, campaign changes, and more.

One unique aspect: Letstrike didn’t confine themselves to just English or a single region. They have native speakers on their team who can do cold outreach in Spanish, French, German, or Italian. This is actually a huge draw for their clients, who might want to break into the European or Australian markets. The challenge, though, is that each language might require a separate domain or subdomain with its own warm-up. Because, guess what, sending Spanish emails from a domain that’s brand-new could set off red flags for spam filters.
But with Smartlead: They could systematically spin up new subdomains for each language or region, warm them up, and manage them from that single Master Inbox. If an inbox has a problem, the dashboard flags it. They rotate to a new address, tweak the sending times, or run a deeper deliverability audit. No more guesswork or manual patchwork solutions.
When asked about a favorite success story, Charles recalled a Spanish software reseller (Google partner) that needed a serious inbound of leads. They’d never used cold emailing in a formal sense. Letstrike built a campaign in multiple Spanish dialects—even Catalan—across different target industries, hooking them up with carefully segmented sequences through Smartlead. The result was 300 qualified leads over six months. The client closed 70 deals from that wave alone. For them, that’s game-changing.
Max’s perspective: “Sure, not all clients see that same ratio, but it shows what’s possible if you do it right—right domain warm-ups, relevant messaging, triggered steps, local language personalization.” Because the synergy of a tool like Smartlead plus Letstrike’s methodology can open new markets very quickly.
Of all Smartlead’s goodies, here’s what Charles and Max say they rely on most:
Both Charles and Max reminisced that once upon a time, it was enough to do Google Sheet merges. You might insert a few placeholders, send 300 daily from your personal Gmail, and still get decent replies. But times changed: domain blacklisting grew stricter, spam filters more thorough, and competition soared. Now you actually need advanced domain health, or your bounce/spam complaint ratio can kill everything in a week.
Their main lesson: “We see a lot of people do cold emailing the wrong way, spamming 10,000 random leads with no triggers or personalization. That might have worked in 2019, but no longer.” For Letstrike, the synergy of new technologies plus a platform like Smartlead let them maintain the high domain rep they need to keep pumping out leads for 500+ clients.
No platform is perfect, and Letstrike’s founders do have suggestions for how Smartlead could improve:
1. More Intuitive for Non-Tech Users: Because Letstrike runs a “done-for-you” approach, sometimes they’d like to hand over partial control to a client. They find that if you’re not an “email nerd,” the Smartlead interface can feel daunting. They might prefer a simpler UI for business owners.
2. Analytics / Exporting: They want an easier way to filter leads across multiple campaigns, or do advanced searches to export just the positives for a certain client, etc. Some improvements in global analytics or search filters could help.
3. Integrations with Multiple HubSpot Accounts: Letstrike’s clients sometimes each have a separate CRM environment. Plugging them all into Smartlead can get messy. They’d love more robust multi-CRM integration.
Still, these are more “nice to have” improvements for an advanced user scenario. For the typical agency or power user, Smartlead’s feature set is already comprehensive.
As Max says: “The best approach is no approach if you can’t handle domain meltdown. The second best is something like Smartlead that’s built from the ground up for deliverability at scale.”
1. Go All-In on Domain Warm-Up: Letstrike is living proof that if you want to scale to 500+ clients, you can’t skip domain rotation, separate subdomains, and a careful ramp-up strategy. Tools like Smartlead do it seamlessly.
2. Localization & Relevance: Even the best platform won’t help if your content is generic. Letstrike’s multi-language approach with region-specific angles is how they break into markets across Europe (and beyond).
3. Centralized Management: If you have 100 or more clients, you can’t keep track of everything in random spreadsheets or seat-based logins. Letstrike avoided an admin nightmare by choosing a platform that’s built for agencies from day one.
4. Keep Innovating: The environment is constantly evolving – so is spam detection. Letstrike invests in new multi-channel expansions (like LinkedIn or SMS) and leverages data from tools like Clay or K-Reach. The result is that they remain relevant, even as old methods get hammered.

So how do you go from zero marketing budget to half a thousand paying clients in a few short years? For Charles and Max, it’s the combination of a bulletproof outbound methodology, multi-lingual angles, and a deliverability-focused tool like Smartlead that orchestrates it all. They emphasize that it’s not just about the quantity of emails; it’s about the right quantity, timing, domain rotation, and personal touch.
Charles’s final note: “I started in cold email with a Google Sheet hack. Now we run everything from a single platform that handles hundreds of clients, multiple domains, advanced analytics. That’s leaps and bounds from the old approach. And it’s let us build an entire business that stands on its own legs, purely from cold outreach.”
If you’re an agency or a B2B software outfit that’s feeling the deliverability crunch, maybe it’s time to take a page from Letstrike’s playbook. The next time you’re swamped in your seat-based, not-so-scalable tool, or your domain is flirting with the spam folder, remember: there’s a platform designed with agencies in mind - Smartlead. And according to Letstrike, it’s a game-changer for anyone chasing big volumes and big results – without the big risk of domain meltdown.
I write about cold outreach, sender reputations, and all the email things you Google at 2 am so you don’t have to.
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Founder, StackOptimise
Smartlead's combination of automation, unlimited inboxes, and easy campaign management has completely transformed how we run cold email campaigns.
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Founder, Cold Email Hackers

We have about 15 companies and we use Smartlead for all of them.

Founder, DutchSave Media

One of the things I love about using Smartlead is the deliverability feature. If they landed in the bounce or spam folders, we could resolve this quickly.

Co-Founder, Growth Today

I want to continue to use Smartlead to make operations more seamless - the plan is to bring more clients here and build more SOPs.

Founder, FueltoFly

Smartlead listens to the agencies and customers and builds according to what people want, that has really made things easier for us.

Founder, OutboundSync

We build an infrastructure product, and OutboundSync communicates with Smartlead itself. I love the webhook and API. They're really well done and keep getting better.

Founder, Axoleads

With SmartDelivery, you can put all of that in the hands of the tool. It ensures your emails land in inboxes, and by running a simple test, you can see if you're hitting the mark.

Founder, Claygen
Deliverability is the cornerstone of cold email outreach. You could have the best email copy in the world, but if no one is seeing it, it's useless. I really love the feature where you can actually give client accesses to your clients.

Co-Founder, Cymate

I do not want to switch to another software. Pick a solution you trust, stick with it, and keep refining your copy.

CMO, Avalanche Capital

Managing large volumes of emails through multiple inboxes used to be a logistical nightmare. With Smartlead, the process is seamless. We book thousands of discovery calls through cold emails. These campaigns are generating leads at a scale we never thought possible.

Founder, Growth Engine X

We came for the unlimited inboxes, and we stayed for the API. 1.5M cold emails/month, 7,767+ inboxes managed.

Head of Community & Ecosystem, TxtCart

You cannot replace having 10,000 touches with potential clients. When you have that much distribution and reach, you really start to see incredible results. The simplicity of Smartlead made all the difference. It doesn't require you to be a technical wizard.

Founder, Hyperke

Smartlead has been a game-changer for us. It increased our appointment volume, improved ease of use, and offered valuable features. 80% increase in appointments/month, peak of 276 appointments in a single month.

Founder, Kinetyca

Smartlead has been our cold email backbone from day one. The platform evolves constantly, keeping pace with how deliverability and personalization need to work today. 21% overall reply rate, $175K in 4 months for multiple B2B clients.

Founder, Reachflow

Smartlead is centered around deliverability and constantly evolving. Their API is not like any other platform. Smartlead covers all our needs. The focus on core features like deliverability and API integration is unmatched.

CEO, Halfwarm

Our approach to crafting conversational emails led to reply rates that many of my peers thought were unattainable.

Co-Founder, letstrike

We've grown on zero capital, zero marketing, purely cold emailing - and that's the story we love to tell. The best approach is no approach if you can't handle domain meltdown. The second best is something like Smartlead that's built from the ground up for deliverability at scale.

Founder, Fenixtal

Smartlead's white-labeling and automation let us punch above our weight. The 12M euros sales potential? That's what happens when you combine human creativity with Smartlead's precision.

Co-Founder, Digital Creativs

Nine out of 10. Ninety percent of our clients are on Smartlead unless they come in with an existing setup. That's the default.

Co-Founder, BuildingReach

At the end of the day, you have to take a bet on one tool or another. It was a no-brainer taking that bet on Smartlead. We had to even turn down the volume of our marketing campaigns - Smartlead was capable of driving more volume than our sales team was able to fulfill.

Founder & MD, Prospectiv

Since starting the business in January of this year, we've already generated $200K in sales exclusively from cold email. Smartlead has been central to our operations and has exceeded our expectations.

Founder, Growthlynk

There's so much stuff built on top of it. I would be dead if I had to rebuild it with another tool. I can manage hundreds of senders easily. I can send hundreds of thousands of emails.

Founder, Corebits

The platform's HubSpot integration, real-time Slack updates, and advanced campaign customization have been game changers for our business and our clients'.

Founder, Apex Ascension

From day one, we've never used anything else.

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