How Aircall used PartnerStack to drive 8% of inbound leads in under a year

Aircall started as a cloud-based phone system. Today, it’s something bigger.

Trusted by more than 23,000 companies, Aircall has evolved into a full customer communications and intelligence platform — one that integrates with the tools sales and support teams already rely on, from Salesforce and HubSpot to Intercom and Slack. With the launch of AI-powered features like AI Voice Agent, AI Messaging Agents and AI Actions, the company is now moving decisively into the agentic AI space, bringing intelligent automation to how businesses talk to their customers.

For Maggie McCarthy, Global Partner Marketing Program Manager, partnerships are central to how the company is diversifying growth — with 2,400 channel partners globally and a fast-growing affiliate program lifting Aircall into new markets and customers.

By launching an affiliate program — and trusting PartnerStack to power it — McCarthy grew Aircall’s affiliate base from zero to 300+ affiliate partners in under a year. Now, affiliates drive 8 per cent of the company’s total volume of inbound leads.

Here’s how she did it.

When the playbook stops working, you build a new one

For Aircall’s marketing team, inbound was the primary source for leads — paid ads on Google and LinkedIn kept the pipeline moving. It was a solid strategy. But as costs rose and MQLs started softening, inbound alone wasn’t going to cut it if they wanted to keep growing.

“We needed to diversify away from inbound methods,” McCarthy says. “Direct traffic is getting more expensive.”

Affiliate marketing was the move. To keep the strategy data-driven, the team did their research, speaking with potential affiliate partners and publications to stress-test the idea. The feedback was consistent. “The majority of them said that they worked on the PartnerStack Network, and they’d prefer to work on the PartnerStack Network,” McCarthy says.

And diversifying away from paid media wasn’t the only goal. Boosting Aircall’s visibility across AI search platforms and LLMs was a growing priority too — and affiliate marketing was a natural way to tackle both.

There was just one catch: this was a one-person show, and McCarthy still had channel partners, alliances and more to run. Whatever they built for affiliates had to run lean.

By mid-last year, with inbound costs continuing to rise, waiting was no longer a good option. McCarthy was ready to act.

See also: Why your affiliate program is also an AI visibility strategy.

More than a platform: a partner

Enter Aircall’s new affiliate program. To build it right, McCarthy wasn’t just looking for a platform. She was looking for a partner.

At first, PartnerStack wasn’t the obvious choice. PartnerStack had been part of Aircall’s tech stack for years, but only used to handle partner commissions.

Partner feedback from the team’s research, however, pointed in the same direction — potential affiliates and publications consistently said that the PartnerStack Network was where they wanted to be. And product feature updates like marketplace discoverability and an AI search tool indicated that PartnerStack was moving at Aircall’s speed when it came to shifting with the broader marketing ecosystem.

But Aircall’s choice was about more than technology — it was about the people. McCarthy points to PartnerStack’s customer success team as a deciding factor. “Bianca and Jess historically have always been so responsive to us, even when we weren’t predominantly using PartnerStack,” she says. “From a trust standpoint, that was a really important factor.”

For a team of one managing multiple partner channels, that kind of relationship isn’t just nice to have. It’s the whole point.

The next step: Aircall committed to a six-month trial period, leveraging PartnerStack’s service offering to help run the program alongside McCarthy. With the right platform, the right people and the right setup, it was time to see what they could build.

You might also like: How to build an affiliate partner program with integrity.

0 to 300+: the affiliate program takes off

Since launching in October 2025, Aircall’s affiliate program has grown from zero to more than 300 affiliate partners — all without a lot of heavy lifting on Aircall’s end.

“From an affiliate standpoint, partner recruitment has been massive,” says McCarthy. “We’ve done one social post, and we have a landing page on our website, and that’s the extent of which we’ve pushed.” All of those affiliate partners were sourced through PartnerStack.

A big part of this early success? Referral links. “Referral links are an incredible feature that not a lot of partner platforms that I’ve worked with have in the same way that PartnerStack does,” McCarthy says.

The reason? Being able to generate a referral link that works across any form on the Aircall domain — from existing pages to brand new product launches — meant the program could scale without having to rebuild infrastructure every time.

The affiliate channel is already outperforming on cost, with an ROAS sitting at 0.274. “Our ROAS is the highest from any channel,” McCarthy notes — and affiliate leads are coming in at a fraction of what traditional inbound channels cost. It’s also delivering on the MQLs that Aircall was after, with a 63 per cent qualified-to-won rate, and serving up 8 per cent of the company’s total inbound lead volume.

This means that not only is the affiliate program more cost effective than paid ads, it reduces Aircall’s dependency on other inbound methods, McCarthy adds.

See also: How to attract better quality affiliates to your program.

The team behind the team

Building a global affiliate program solo is no small task — which is why, for McCarthy, one of the biggest factors in making it work has been PartnerStack’s customer support.

“I’m a team of one, so having Jess and Bianca is like having my own team,” she says. “I’ve never worked with another vendor in my career that I felt like I’m part of their team and they’re part of my team — my success is their success, their success is mine.”

For a team of one juggling channel partners and alliances in addition to affiliates, that kind of relationship and trust is a difference-maker.

“That’s the biggest win for me — the customer support and the trust that you have within your team — I haven’t experienced it in another company before,” McCarthy says.

What’s next: partners in an AI-first world

Aircall isn’t abandoning its roots as a phone solution, but it isn’t standing still either, with a subtle rebrand, a clear shift toward the agentic AI space and a product roadmap moving fast.

“It’s really exciting to be at a company that is genuinely within the virtual agent space,” McCarthy says, “and to see how the world of tech is going to evolve alongside our integration partners.”

For McCarthy, the affiliate program is a big part of how Aircall will bring partners along that journey — getting them excited about new products, capabilities and ways of serving customers. And the program itself? It’s just hitting its stride.

Aircall’s AI visibility results are already compounding. “The brand is now being surfaced organically across every major AI platform buyers use to research call software, including all LLMs,” she says. “In short, when prospects ask AI ‘what’s the best phone system,’ Aircall is increasingly part of the answer, and the content engine driving that is still scaling.”

As for what comes next, McCarthy doesn’t pretend to have all the answers, but she’s watching closely:

“It’ll be interesting to see how partner programs evolve to match the technology and product shift that is happening. I’m not really sure what that looks like, but I’m definitely intrigued.”

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