Heirloom

formerly Heirloom Carbon

Restoring balance to our atmosphere by removing 1 billion tons of carbon dioxide

San Francisco, United States · Founded 2021 · $256.0M raised

Employees
51–200
Founded
2021
Business Model
B2B
Total Funding
$256.0M
Last Round
$150.0M Series BDec 2024
Rounds
4

Totals include recorded grants and other qualifying funding, not just equity. What counts toward funding.

About

Heirloom is a direct air capture (DAC) company dedicated to permanently removing carbon dioxide from the atmosphere using a low-cost, scalable technology based on carbon mineralization. The company accelerates the natural process by which limestone (calcium carbonate) absorbs CO2, using engineered systems to cycle limestone through heating and re-exposure to air. Heirloom operates America's first commercial DAC facility and has signed major carbon removal contracts with Microsoft, Shopify, and United Airlines, targeting removal of 1 billion tons of CO2 by 2035.

Summary

Heirloom is a Sustainability company based in San Francisco, United States, founded in 2021. It has raised $256.0M in total across 4 rounds, most recently a $150.0M Series B round in Dec 2024. Investors include Lowercarbon Capital, Breakthrough Energy Ventures and Carbon Direct Capital Management.

Tech & App Stack

3 technologies & apps tracked

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Funding History

Series BSeries BDec 2024
$150.0M

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Funding: Seed through Series B. Amounts, valuations, and investors where available.

Investors

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