In times when transitioning from a linear carbonintensive economy into a sustainable circular economy is an urgent need, bio-based nanoparticles such as nanochitins are attracting an increasing interest for value-added products. Fungal chitin nanofibril (ChNF) isolation show a reduced CO 2 footprint over crustacean shell-derived nanochitin, which requires harsh chemical treatments. However, the viability and practical implementation of ChNFs from fungi may depend on the manufacturing costs. Accordingly, here we assess the economic feasibility of a pilot-scale fungi-derived ChNF isolation comprising chitin nanofibrils with covalently bonded β-glucans. Required capital investment, production costs, minimum product selling prices, and payback periods for ChNF isolation are obtained considering a refinery plant treating 3000 kg of fresh mushroom daily and located in Bilbao, north of Spain. The proposed business model offers clear signals of technical, economic, and commercial viability for the pilot industrial plant format, under relatively conservative technical assumptions. In particular, a total capital investment for a pilot-scale biorefinery is estimated at ∼1.10 M€ for ChNFs, where a working capital of ∼380 K€ indicates good short-term financial health of a company. A payback period of 11.3 years with estimated minimum selling price of 212 €•kg −1 for the year 2024 is obtained, which can be lowered to 106 €•kg −1 in a scenario where the chitin extraction yield is doubled. This value remains below the selling value of nanocelluloses from leading manufacturers, making ChNFs from fungi a competitive alternative to develop novel materials addressing the challenges of renewability, environmental sustainability, and functional properties. In particular, the ease of isolation with minimal use of chemicals is a significant economic advantage, although the low yield is a noteworthy drawback for profit after taxes. A sensitivity analysis is conducted by considering five scenarios that can occur upon biorefinery operation. These results highlight the bright future of fungal nanochitin to meet market demands on sustainable materials, especially in value-added applications such as energy storage and biomedicine, where high selling prices are affordable. As applications of fungal nanomaterials are gaining momentum, the techno-economic assessment here shown provides cues for the practical implementation of nanochitin into a sustainable society based on a circular bioeconomy.