April 14, 2025

Navigating the world of accelerators

Disclaimer: this article is based on research conducted by the B4i team and draws on recent studies, including Jacopo Faini’s master thesis on university-based accelerators (Impacts of University-based Accelerators on start-ups’ development: the Bocconi for innovation case, 2022) and other sources explicitly referenced throughout the text.

The global startup ecosystem has undergone a profound transformation over the past two decades — and one of the most significant innovations has been the rise of accelerators. Once a niche concept, accelerators are now everywhere, with more than 3.000 are active worldwide (source: Jacopo Faini's master thesis, 2022), spanning every continent, industry, and support model.

For early-stage founders, this abundance can be both exciting and overwhelming. On the one hand, accelerators promise mentorship, visibility, and funding — the lifeblood of any young business. On the other hand, with so many options out there, how do you choose the right one for your startup? And more importantly, how do you know if joining an accelerator is even the right move for you?

What is an Accelerator?

Let’s start with the basics. An accelerator is a temporary, cohort-based program designed to fast-track the growth of early-stage startups. Participants receive structured support — typically over 3 to 6 months — in several forms: mentorship, business training, workspace, networking opportunities and often seed funding or access to investors. The idea is simple but powerful: to compress years of learning, validation, and connections into few months — with the aim of preparing startups for scale and funding.

Accelerators and incubators differ in structure, goals, and business models. Accelerators are typically short-term, cohort-based, selective, and investment-driven, offering capital, mentorship, and strategic support in exchange for equity.

Incubators, by contrast, often provide flexible workspace and basic support services without equity investment, making them more infrastructure-oriented than growth-oriented.

Y Combinator: Where It All Began

No discussion of startup accelerators is complete without mentioning Y Combinator. Founded in 2005 by Paul Graham and a small team of technologists, YC introduced a radically new approach: short, high-intensity programs focused on product development, traction, and investor readiness.

With an acceptance rate of less than 1% (source) — lower than Harvard’s — YC became the launch pad for companies like Airbnb, Dropbox, Reddit, and Stripe. But YC’s most lasting contribution may be cultural. It changed the perception of what early-stage support could be: not just desks and Wi-Fi, but a community of founders, direct access to experienced operators, and proximity to capital. It turned acceleration into a mindset and laid the foundation for what an accelerator could (and should) offer. Its formula — a cohort-based structure, hands-on mentorship, and demo day — quickly became the standard, inspiring thousands of accelerators worldwide.

Generalist vs. Vertical Accelerators

Not all accelerators are built the same. As the model has matured, many programs evolved to specialize — shifting from generalist approaches to vertical accelerators, focused on specific industries or technologies. The goal? To offer founders more targeted support, deeper expertise, and relevant connections within their sector. Generalist accelerators like Y Combinator welcome startups from a wide range of industries, often focusing on core business skills, growth tactics, and fundraising strategy. They’re great for founders who want broad exposure or still exploring use cases. Vertical accelerators, on the other hand, cater to startups operating in well-defined sectors such as fintech, healthtech, sustainability, or fashion-tech. This kind of accelerators aren’t for everyone — but if your startup operates in a complex, regulated, or niche industry, joining a sector-specific program can give you a significant advantage.

University-Based Accelerators

University-Based Accelerators (UBAs) emerged just over a decade ago, as part of a broader shift toward more entrepreneurial universities. Today, they are transforming higher education institutions from passive knowledge producers into active players in the startup ecosystem — bridging research and industry. They typically combine the benefits of a traditional accelerator with the unique resources of a university: academic expertise, research infrastructure, a steady flow of talent and strong alumni networks. What sets UBAs apart is not just what they offer, but why they exist. Many are designed to support startups with both economic and societal impact, and they often provide non-dilutive funding, and hands-on mentorship from professors and alumni entrepreneurs. Recent research shows that startups supported by UBAs demonstrate higher survival rates and better performance in terms of revenue and employment — particularly in the two years following acceleration (source: Jacopo Faini master thesis, 2022; Romani, 2023). These programs are also seen as enablers of regional innovation ecosystems, thanks to their strong ties with local governments and private investors. Notable European UBAs include:

B4i – Bocconi University (Italy);
PoliHub - Politecnico di Milano (Italy);
Luiss EnLabs - LUISS University (Italy);
I3P - Politecnico di Torino (Italy);
Almacube - Università di Bologna (Italy);
CBS - Copenhagen School of Entrepreneurship (Denmark);
Esade Entrepreneurship Institute - Ramon Llull University (Spain);
HEC Paris Innovation & Entrepreneurship Center - Hec Paris Business School (France);
LSE Generate - London Business School (UK).

Together, these programs demonstrate how universities are actively reshaping their role — from knowledge producers to startup enablers, nurturing ventures that combine research, entrepreneurship, and real-world impact.

Do Accelerators Really Work?

The short answer is yes — but with caveats. Startups that go through an accelerator program are 23% more likely to survive after five years compared to those that don’t (source). However not every accelerator is right for every startup. The compressed timeline can create pressure to scale prematurely. Some programs take equity without delivering real value. And others may prioritize visibility over substance.

Joining an accelerator can be one of the most important decisions in your entrepreneurial journey - one that will shape your trajectory, your network, and your startup's ability to scale. To conclude, we asked Jacopo Faini, Head of Acceleration at B4i, what questions a founder should ask himself or herself when choosing the acceleration program that is right for them. “The best accelerator for your startup isn’t necessarily the most famous one — it’s the one that understands your vision, challenges your assumptions, and gives you exactly what you need to move faster, smarter, and more confidently. Always remember that accelerators must decrease startups’ initial barriers, without distracting founders from being founders”. Here's a list of questions to ask yourself to choose the right programs:

Is the program fitting with the stage in which your startup is in? Most of the time, timing and maturity of the team and the solution they are proposing are influencing the participation to certain accelerators;
Do you need horizontal support from a generalist accelerator or an industry-focused vertical accelerator? Consider if you need an extensive 360° support on your technology and/or startup fundamentals, or a specific focus in diving deep in the industry with certain corporates involved in the program;
How strong is the network and the community of the accelerator? The true value of an accelerator comes from the network of founders and stakeholders it can activate for you, and that’s why university-based accelerators are among the best in doing so. If the program is held in person, the network effect will skyrocket!
Are the investment conditions fair and transparent? This may seem obvious, but as one of your first investors, you want to have a strategic partner with equity reflecting as much as possible the “cash-only” investment that will support you in subsequent rounds with possible follow-ons. You must think about your cap-table from day0, so take that into consideration. If the program offers subsequent portfolio support with clear activities, it is a great plus;
Finally, always ask the accelerator’s team what they can support you with and how much they can customize the activities based on your needs. An accelerator with smaller cohort and more customized support can support you better in specific needs you may encounter along the journey.