Which startups have raised the most funding in the nuclear fusion market?

A constantly refreshed ranking of the top startups in the nuclear fusion market, ranked by total cumulative funding raised

A quick summary table

Metric	Value
Most funded nuclear fusion startup	Commonwealth Fusion Systems, $2.8B raised
Second most funded nuclear fusion startup	Neo Fusion, $2.0B raised
Largest funding round	China Fusion Energy, $1.6B strategic equity round
Median funding	About $42M across the ranked reliable dataset
Share of funding captured by the top 10	About 78% of total tracked funding
Median time since last round	About 13 months
Startups that raised funding in the last 12 months	32 startups
Total tracked nuclear fusion funding	About $15.6B across reliable funded companies
Nuclear fusion startups above $1B raised	5 companies
Nuclear fusion startups above $100M raised	24 companies
Most capital-intensive nuclear fusion funding segment	Reactor-first platforms, especially tokamak, pulsed magnetic, and inertial fusion companies

Top startups in the nuclear fusion market ranked by total funding raised

Here is an updated table that ranks the top startups in the nuclear fusion market based on the total amount of funding they have raised to date.

The table also includes the total number of funding rounds, the date and size of the latest round, the financing type (e.g. Series A, equity financing), key investors, the startup’s current status (active, IPO, acquired, or shut down), and a confidence score based on the data collected (we excluded startups with very low data confidence, to make sure everything is reliable).

Key funding trends in the nuclear fusion market

A few word about our methodology

As you can see, we built a database that ranks nuclear fusion startups based on their total cumulative fundraising. To create this ranking, we reviewed many sources and cross-checked information across multiple places.

Whenever possible, we prioritized official company communications, since official announcements are usually the most reliable source for fusion funding amounts. When those were not available, we relied on reputable industry sources such as TechCrunch, Crunchbase, Financial Times or Forbes (to name a few).

We excluded random blogs, unverified websites, and any sources that could not be validated.

When funding rounds were announced in other currencies such as euros, Swiss francs, Singapore dollars, Australian dollars, Chinese yuan, Japanese yen, or rupees, we converted them into approximate USD equivalents for consistency.

Sometimes different sources report slightly different numbers, or the exact round size is not fully disclosed. In those cases, we flag the uncertainty and assign a confidence label to each startup, visible in the last column.

Here is what they mean.

Full confidence: The company’s equity fundraising history can be reconstructed completely from public sources. The rounds, dates, amounts, and key investors are clearly identified, with no meaningful gaps.

Strong confidence: The fundraising history is largely complete and reliable. There may be a small missing detail, such as incomplete investor information or a minor round with limited data, but the overall record is clear.

Partial confidence: The main fundraising rounds can be identified, but the record is incomplete or somewhat mixed. Some rounds may be missing or certain funding events may be difficult to separate clearly.

Low confidence: Public information is too limited, inconsistent, or ambiguous to reliably reconstruct the company’s equity fundraising history.

When the confidence level is too low, we take a conservative approach and exclude the company from the ranking. We don’t want to include data that cannot be reliably verified.

This reflects how we conduct all our nuclear fusion market research.

In a world where LLMs hallucinate and unreliable information is everywhere, our goal is simple: provide data you can trust.

If you want the full detail on a specific calculation, feel free to contact us and we will gladly explain.

Finally, know that we update the dataset once per month, so come back here if you need fresh information.

Who is the author of this content?

NEW MARKET PITCH TEAM

We track new markets so founders and investors can move faster

We build living “market pitch” documents for emerging markets: from AI to synthetic biology and new proteins. Instead of digging through outdated PDFs, random blog posts, and hallucinated LLM answers, our clients get a clean, visual, always-updated view of what’s really happening. We map the key players, deals, regulations, metrics and signals that matter so you can decide faster whether a market is worth your time. Want to know more? Check out our about page. You can also follow us on Instagram or on Facebook.

How we created this content 🔎📝

At New Market Pitch, we kept seeing the same problem: when you look at a new market, the data is either missing, paywalled, or buried in 300-page reports that feel like they were written in the 80s. On the other side, LLMs and random blog posts give you confident answers with no sources, and sometimes they just make things up. That’s not good enough when you’re about to invest real money or launch a company.

So we decided to fix the experience. For each market we cover, we build a structured database and update it on a regular basis. We track funding rounds, fund memos, M&A moves, partnerships, new products, policy changes, and the real activity of startups and incumbents. Then we turn all of that into a clear “market pitch” that shows where the opportunities are and how people actually win in that space.

Every key data point is checked, sourced, and put back into context by our team. That’s how we can give you both speed and reliability: fast coverage of new markets, without the usual guesswork.