Eos Energy Enterprises (NASDAQ:EOSE) reported fourth-quarter and full-year 2025 results marked by rapid revenue expansion, improving operational efficiency and a strengthened balance sheet, as the U.S.-based long-duration energy storage developer targets a transition toward scalable, profitable growth.
The company, which manufactures zinc-based battery storage systems domestically, delivered record quarterly revenue and introduced initial guidance for 2026, reflecting growing demand for long-duration energy storage solutions.
Chief Executive Officer Joe Mastrangelo described 2025 as a pivotal year for the business.
“2025 was a structural turning point for Eos. We accelerated production, expanded annual capacity to 2 GWh, delivered record quarterly revenue, strengthened our cash position to over $600 million, and secured more than $240 million in fourth quarter bookings across diversified markets,” Mastrangelo said. “While disappointed in not meeting revenue expectations, execution improved significantly as 2025 progressed, and we exited the year with clear operational momentum.”
He added that the company’s near-term focus centers on scaling efficiently and improving profitability. “In 2026, our focus is on disciplined scale and margin improvement — driving manufacturing efficiency, improving unit economics quarter-over-quarter, and converting our backlog into high-quality revenue. With a strengthened balance sheet and improving cost profile, we believe we are positioned to transition from accelerated growth to sustainable value creation.”
Fourth-quarter performance
Eos generated record fourth-quarter revenue of $58.0 million, representing a 90% increase from the prior quarter and roughly eight times higher than the same period a year earlier. Growth was supported by manufacturing automation, operational efficiency gains and quality improvements across production lines.
The company reported a gross loss of $54.4 million, though margins improved significantly year over year as product economics strengthened. Adjusted gross loss, excluding stock-based compensation and depreciation, totaled $49.1 million.
Net loss attributable to shareholders was $120.5 million, while adjusted EBITDA loss widened to $71.5 million compared with $44.6 million a year earlier, despite notable margin improvement reflecting operational progress.
Eos ended the year with total cash of $624.6 million, including restricted cash, providing substantial liquidity to support expansion plans.
Order backlog reached $701.5 million, equivalent to 2.8 GWh of contracted storage capacity, up 9% sequentially, while the company’s commercial opportunity pipeline expanded to $23.6 billion, rising 64% year over year.
Full-year 2025 results
For the full year, revenue climbed to $114.2 million — more than seven times 2024 levels — driven by scaled production and a 609% increase in customer deliveries.
Gross loss narrowed in margin terms to $143.8 million as higher manufacturing volumes and declining Z3 production costs improved unit economics. Adjusted gross loss totaled $128.5 million.
Net loss attributable to shareholders reached $969.6 million, largely reflecting non-cash accounting items totaling $746.8 million related to fair-value adjustments, capital structure optimization and stock-based compensation.
Adjusted EBITDA loss for the year was $219.1 million, compared with $156.6 million in 2024, though margins improved substantially due to operational efficiencies and cost reductions.
2026 outlook
Eos expects full-year 2026 revenue to range between $300 million and $400 million, signaling confidence in accelerating commercial deployments and backlog conversion.
Operational and technology milestones
The company exited 2025 with annualized production capacity of 2 GWh following continued automation, subassembly integration and manufacturing optimization. Although the milestone was achieved several weeks later than planned, production output accelerated sharply during the second half of the year.
Eos also launched Indensity™, a next-generation modular energy storage architecture designed to deliver up to 1 GWh of storage per acre — roughly four times the density of many conventional battery systems. The platform incorporates flexible spatial configurations aimed at improving safety, site adaptability and cost competitiveness while maintaining long-duration performance advantages.
Commercial momentum and balance sheet strengthening
During 2025, Eos secured more than $240 million in fourth-quarter bookings across eight customers and nine projects totaling nearly 1.1 GWh of contracted capacity. Demand spanned commercial and industrial customers, distributed energy portfolios and large utility-scale projects.
The company also strengthened its financial position through a convertible senior notes offering and a concurrent equity issuance, generating approximately $580.5 million and $458.2 million in proceeds, respectively.
Key outcomes included:
- Retirement of $200 million of 2030 convertible notes
- Reduction of annual interest expense by roughly $3 million
- Addition of approximately $474 million in net cash
- Extension of corporate debt maturities to 2030 and beyond
Management said that, given its improved liquidity and cost trajectory, substantial doubt regarding the company’s ability to continue as a going concern has been removed.