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Inside a Castellum Accelerator

Castellum accelerators have one goal: to help entrepreneurs succeed. During each three-month program, we surround companies with the best mentors and an unrivaled network of corporate partners, investors, and alumni. We provide funding and fundraising opportunities, workshops and curated resources, not to mention countless moments where you can learn from your peers. It’s a proven model that’s helped build thousands of successful companies, all over the world.

Ready to apply? Select the accelerator of your choice to get started.


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Key Information

All our best tips, tricks, insights, and explanations around what a Castellum accelerator is and how to apply:

What To Expect From the Three Months Of the Accelerator

The Application & Interview Process

How To Choose the Right Accelerator For You

What Are We Looking For?

Before You Apply, Engage

Investment Terms

How We Help Entreprenuers succeed

Want to know what it’s really like inside an accelerator? In this video, Castellum Cofounder breaks down the three-month program, and founders weigh in on what made the experience so transformative for their companies.

“ Every single one of our investors I met through Castellum. Without Castellum, we would not have raised anything, would not have hired the 14 employees that we have today. Basically, without PSTO and Castellum would still just be me. “

Ana-Maria Pruteanu,Founder and CEO of PSTO and Castellum

Accelerator FAQ

You’ve got questions. We’ve got answers. Check out our Frequently Asked Questions.

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