August 25, 2023

The European startups in Y Combinator’s S23 cohort

The US accelerator has taken on 108 founders from Europe

The Y Combinator team give a talk

The proportion of European founders taking part in Silicon Valley accelerator Y Combinator’s summer cohort this year rose to 21% — up from 13% in the winter cohort and 18% in the summer of 2022. 

Y Combinator confirmed with Sifted that 108 European founders are building their startups with the famed 18-year-old accelerator, out of 517 in total. That’s up from the 72 that took part in YC’s 2023 winter cohort — where 542 founders took part overall.

The accelerator has seen a rise in European participants since it went online during the pandemic. While YC has since shifted back to an in-person affair, it doesn’t seem to have deterred European founders from upping sticks and moving to the US for a few months.


YC’s summer programme runs from June to August and is one of startupland’s most esteemed company builders. It was one of only two accelerators that a Sifted survey of 20 top-tier VCs rated as worth taking part in — the other was Entrepreneur First — and the company says that 39% of its startups go on to raise a Series A. 

So far, 27 Europe-based startups have announced themselves publicly as part of the summer batch, according to YC’s website.

Here are the startups taking part in Y Combinator's summer cohort.


Slicker: London-based Slicker is a payments processing platform for large businesses.

Latent Space: The London-based startup helps teams analyse spreadsheet data with its AI assistant. Munich-based startup is an AI-powered customer service tool, helping teams reply to customers in an instant.

Atla: London-based atla is building an AI assistant for legal teams. Copenhagen’s helps developer-facing companies — like OpenAI and Airbyte — build AI support bots.

Subsets: The Copenhagen-based startup is an AI-driven customer retention platform for subscription businesses.

Haven: A Berlin-based startup helping companies run large language models on the cloud.

Quack AI: The French startup is an AI-powered developer tool for software companies that want to run open source projects.

Osium AI: A French startup helping R&D engineers formulate and characterise advanced and sustainable materials with its AI platform.

FlowiseAI: The Irish no-code startup helps companies build large language models based on their own data.

CodeStory: A London-based developer tool building a platform to automate workflows.

Solve Intelligence: A London startup which uses AI to write patents.

Parea AI: A Berlin-based developer tool for debugging and monitoring large language model (LLM) applications in development.

Climate tech

Orbio Earth: Berlin-based Orbio uses satellite images to track methane emissions from oil and gas companies. It sells the data to investors looking to back companies in the sector.


Elyos Energy: The London-based startup helps businesses optimise their energy usage by automatically buying electricity when cost is lowest.

HyLight: Paris-based Hylight is building autonomous airships that can monitor leaks on pipelines and defects on power lines. 


Tiptap: Berlin-based Tiptap is building open source content editing and collaboration tools for developers.

Aglide: London’s Aglide is a password manager for startups, which helps companies track employee apps, costs and usage.

Upstream: A Paris-based messaging app for teams built on top of email.

Unhaze: The Copenhagen-based startup is a tool for sales teams that helps them find leads most likely to close. Zurich’s SID is a developer tool enabling companies to integrate customer data with their own large language models. 

Langdock: A German GDPR compliance tool for companies that use ChatGPT.


Capi Money: The London-based startup is a payments processor for African businesses.

Fragment: A French startup helping fintechs automate compliance operations.


Healthtech-1: The London-based startup automates processes in healthcare systems, and says it’s currently working with 100 NHS primary care practices. 

Sohar Health: London’s Sohar Health is a SaaS platform for behavioural health companies that automates workflows, verifies insurance claims and helps increase patient intake.

MediSearch: A London-based search engine for health queries.

Nanograb: London's Nanograb is a drug discovery startup which uses AI to create binders — compounds which help stick together powders and other ingredients that make up a drug.

Kai Nicol-Schwarz

Kai Nicol-Schwarz is a reporter at Sifted. He covers UK tech and healthtech, and can be found on X and LinkedIn