telli’s $15 Million Seed Automates the Floor It Hired

Berlin’s telli has raised $15 million in seed funding to put AI agents on the customer calls its founders once staffed with people. The round, led by redalpine, takes total funding past $18.5 million.

Finn zur Mühlen and Philipp Baumanns built Enpal’s heat-pump sales unit to 150 people in its first year. Enpal now runs their agents on service bookings.

Redalpine Led a $15 Million Seed for Berlin’s telli

telli announced a $15 million seed round in July 2026, with Mutschler joining existing backers Cherry Ventures and Y Combinator. The cheque is still a seed, 15 months after a $3.6 million pre-seed in April 2025.

THE SEED AT A GLANCE

• The cheque: $15 million, led by redalpine, with total funding now past $18.5 million.
• The date: The company and several European deal desks posted the round on July 23, 2026.
• The product: AI agents on voice, WhatsApp, chat, SMS, and email, with an ops coworker named Charlie.
• The plan: Hire across more than 15 roles in engineering, go-to-market, and customer operations.

Named angels on the cap table include Whirlpool chief executive Marc Bitzer, who also sits on BMW’s supervisory board, Adyen executive Alexa von Bismarck, former Flixbus and Lufthansa director Martin Koehler, and Krischan von Moeller of Paragon Partners. Bitzer’s presence fits a roster that already sells into appliance and home-energy work, not a generic helpdesk.

zur Mühlen is chief executive, Baumanns is chief operating officer, and Sebastian Hapte-Selassie is chief technology officer. Hapte-Selassie studied computer science at Stanford and wrote software at Pitch and N26 before the three incorporated in Berlin in 2024.

A 150-Person Floor Before the First Agent

The product started as a staffing problem. zur Mühlen and Baumanns ran contact-center style sales for Enpal’s heat-pump unit, a business that had to collect house data, file subsidy paperwork, and still get a human on the phone when a quote turned into a conversation. Missed calls piled up. Context died between tools. Headcount was the only lever that worked.

TELLI’S DATES TO THE SEED

1. 2024: The three founders start telli in Berlin after the Enpal heat-pump years.
2. Fall 2024: The company goes through Y Combinator’s F24 batch as a voice-agent tool for B2C teams.
3. April 15, 2025: Cherry Ventures and Y Combinator lead a $3.6 million pre-seed. telli says it has processed close to a million calls with a six-person Berlin team and is growing revenue more than 50% month over month.
4. July 23, 2026: redalpine leads the $15 million seed and total funding moves past $18.5 million.

Baumanns’s Y Combinator profile from the F24 batch still lists the Enpal chapter in one line: he scaled the heat-pump unit of Europe’s largest solar installer, then valued at $2.4 billion, as employee No. 2. zur Mühlen has said they scaled the customer-service people and saw, firsthand, how hard call automation is when the job is winning the next appointment, not answering a FAQ.

That is the joke the round is funding. The same two operators who used hiring as the growth engine are now selling software that takes the repetitive slice of that engine off the board.

Enpal’s Connection Rate Moved From 75% to 90%

Enpal did not stay a founding story. It is a live account. Founded in Berlin in 2017, the company sells solar, batteries, chargers, meters, and heat pumps, and it says more than 100,000 German households now sit on long service contracts backed by investors including TPG Rise Climate and SoftBank. When a customer files a service request, a routing algorithm proposes slots. Humans used to chase the booking.

The old limit was two callbacks in business hours, which produced a 75% connection rate. telli’s agents now confirm the slot, catch the return call, and make 4-5 extra contact attempts after the first try, including evenings and weekends. Enpal’s published results sit in a tight band.

ENPAL SERVICE METRICS WITH TELLI

Lukas McKenzie, the Enpal business development manager who owns the service relationship, said the point of the install was to get account managers off call volume and back onto the cases that actually need a person. Enpal says it did that without adding headcount on dispatch.

telli is flexible, scalable, and customer-centric. With telli, our team stays focused on what really matters.

Lukas McKenzie, Business Development Manager, Enpal

Enpal is now wiring the same agents into pre-sales, sales, and customer service. The company that trained the founders on a 150-person floor is using their software to avoid building the next 150.

What Charlie Does When a Call Goes Wrong

The agents handle the conversations. Charlie is the coworker telli sells to the humans who still run the operation. In redalpine’s investment note, Hapte-Selassie’s engineering group is five people shipping to production 10 to 15 times a day, and the demo that closed the firm was not a lab benchmark.

The platform diagnosed its own failed call, proposed a fix, and completed the second attempt live on real customer data before anyone asked. That is the specimen. A missed booking is not a ticket in a queue. It is a loop the software is supposed to notice, patch, and rerun.

CHARLIE’S JOB ON THE OPS DESK

• Build the agent: Set up voice and message agents and connect them to calendars, CRMs, and the rest of the stack.
• Watch the calls: Review conversations, flag failures, and point to the turn where a booking died.
• Change the script: Run experiments and push a fix without waiting on a research sprint.
• Do the chores: Qualify leads, book appointments, run follow-ups, and close the easy service tickets.

zur Mühlen has been careful with the replacement language. He describes first-touch and peak-hour calls as the work the agents take, with people still on the complex cases. Charlie is the interface for that split. James Smith, head of customer operations at German insurtech Clark, said the speed of those changes is what separated it from other tools his team had tried, and that spinning up a new use case is easy once Charlie is in the loop.

redalpine’s write-up of the founders is blunter than the coworker branding. It says Finn and Philipp automated the exact workflow they ran by hand at Enpal. The seed is a bet that this operating memory matters more than another year in a model lab. zur Mühlen has also said telli is not a research company, and that the model under the agent is not the product the customer is buying.

Parloa’s $3 Billion and Sierra’s $950 Million Round

The category around that product is already expensive. In the same Berlin market, Parloa raised $350 million at a $3 billion valuation on January 15, 2026, a Series D led by General Catalyst that brought its total capital past $560 million. Parloa said it employed 380 people across New York, Berlin, and Munich and had crossed a $50 million revenue mark. Its logos sit in a different register: Allianz, Booking.com, SAP, Swiss Life.

Sierra, the San Francisco company founded by Bret Taylor and Clay Bavor, announced a $950 million round on May 4, 2026, led by Tiger Global and GV, at a $15.8 billion post-money valuation. Sierra said it had reached $150 million in annual recurring revenue and that more than 40% of the Fortune 50 were customers. telli’s seed is a rounding error on either raise.

THREE CHEQUES IN THE SAME CATEGORY

Sebastian Becker, a general partner at redalpine, backed telli anyway after watching the space for some time. Older contact-center names still sit in the same buying conversations, including Genesys, Five9, Talkdesk, and Aircall, and they are adding AI inside products that already own the queue. telli’s answer is not a bigger war chest. It is a narrower beachhead: European B2C operations in which the hard part is the workflow, the language, and the after-hours callback, not a Fortune 50 rollout.

We’ve followed this space for quite some time and the telli founders are the most technically exceptional and complementary team we’ve encountered. The value voice agents will unlock across enterprise automation is immense, and we strongly believe telli is in pole position to capture the opportunity.

Sebastian Becker, General Partner, redalpine

Berlin already holds more than one answer to that opportunity. Parloa is the heavily capitalized enterprise platform. telli is the seed-stage operator tool with energy-installer fingerprints. Both sell agents that talk to customers. They are not selling the same year of the company’s life, and they are not selling to the same buyer.

Enpal, Vaillant, and Viessmann Bought In Early

The published customer list is not a spread of generic SaaS helpdesks. telli says its agents already handle millions of conversations for companies that include Sky, Enpal, Vaillant, and Viessmann, with Clark in the mix on the insurance side. Three of those names sell heat, power, or both. Sky is pay-TV. The pattern is high-volume B2C in markets where a missed call is a missed install, a missed repair, or a missed save, and where German-language voice still has to work on the first try.

telli says revenue grew nine times year over year and names Sky and Enpal among the accounts behind that figure, without giving the starting number. Treat the multiple as a company claim, not a spreadsheet. The more grounded signal is the work those accounts actually bought: appointment setting, lead qualification, follow-ups, and service tickets, on phone and message, with Charlie on the ops desk.

What’s massively impressed us is the speed at which we can make changes. Having Charlie there, compared to all the other tools we’ve seen, lets us move at speed, and spinning up new use cases is super easy.

James Smith, Head of Customer Operations, Clark

That is a different sale from Parloa’s Fortune-200 pitch or Sierra’s bank-and-insurer roster. It is also the sale the founders can do without a translator. They already lived the heat-pump version of the bottleneck, and the first logos look like the industry that taught it to them.

Fifteen Open Jobs and a Broader Channel Stack

The $15 million is earmarked for builders. telli says it will grow engineering and go-to-market, keep developing Charlie, and widen the voice and multi-channel agent layer so a customer can move from a call to WhatsApp to email without the company reconstructing the thread. The careers page listed more than 15 open roles in engineering, GTM, and customer operations when the round went out, and the hiring posts were still the only public follow-up through late summer.

The longer thesis in the founder letter is that consumers will start sending their own agents to talk to companies, and that B2C firms will need agents on their side of that conversation too. Voice is the wedge because that is where Enpal’s floor broke. The next channels are already in the product brief.

Customer-facing operations are becoming too complex to run with the current tools alone. The next generation of consumer companies will need AI that can talk to customers, work across channels, and help teams improve the operation behind every interaction. That is what we are building with telli.

Finn zur Mühlen, Co-Founder and CEO, telli

Enpal is already expanding the same agents from dispatch into pre-sales, sales, and service. For a seed-stage shop, that is the proof that still fits on one floor: the company that once needed 150 people to sell heat pumps is now paying its alumni to take the callbacks.