Series B Funding Diversifies and Grows in 2026

U.S. startups are securing Series B funding that has been steadily increasing after reaching a low in 2023, with the current year off to a strong start, according to Crunchbase News. This diversification spans various sectors, including biotech, robotics, and security, while AI remains a prominent theme but not the sole focus.

Overview of Series B Trends

Annual Series B funding is moving higher following the 2023 low, and round counts are holding steady, which indicates that the pipeline of funded companies remains robust. According to Crunchbase News, investors are favoring a wide range of sectors, with startups like those in biotech and robotics securing significant rounds. While AI-related categories account for roughly half of Series B investment over the past six months, more than a quarter has gone to healthcare and biotech, and about 15% to robotics and hardware-related investments.

Largest Series B Rounds in Recent Months

In the past six months, notable Series B rounds include a $2 billion financing for Reflection AI, led by Nvidia, for developing open foundation models, as well as $600 million raises for Kailera Therapeutics, which focuses on oral treatments for obesity, and Physical Intelligence, an AI robotics startup led by Google’s CapitalG. Crunchbase data highlights these as part of the largest U.S. Series B rounds, showing a trend where a good portion of investment concentrates on favored startups across diverse technologies. A list of the 10 largest Series B recipients from this period further illustrates this variety, encompassing areas like security and software.

Shifts in Round Sizes and Distribution

Average Series B round sizes are increasing, with the average reaching $68 million so far in 2026, marking the highest on record, as charted in Crunchbase data. From 2020 through 2023, there were typically about 150 rounds between $1 million and $10 million annually, but last year saw only 44 such rounds, indicating fewer smaller investments. (As widely known in venture capital, this shift reflects broader market dynamics where capital increasingly flows to more established companies, though this does not directly alter Series B patterns significantly.) According to Crunchbase News, a majority of Series B funding has gone to software-focused companies, and these investments typically target firms with an impressive technological edge or early traction.

Implications for Emerging Managers

Series B investments are not as dramatically affected by capital concentration as later stages, with data showing steady round counts and diversified bets. Per Crunchbase News, this environment suggests that while investors consolidate somewhat, they maintain variety across industries, benefiting startups at this growth phase.