Double Union is supported entirely by donations, membership dues, and volunteers. We would love your support for our makerspace in San Francisco! We hope to serve as a role model and resource for other makerspaces and hackerspaces around the world.

We are a 501(c)(3) nonprofit. Our EIN is 46-3264631, and you can view our public IRS filings by looking up Double Union in the California Registry of Charitable Trusts.

Make a donation

You can make tax deductible one-time or monthly recurring donations via PayPal.

If you'd like to write a check (for example, if you want to donate from your donor-advised fund), you can make it out to Double Union and send it to our mailing address (which is different from our physical address):

Double Union
2443 Fillmore St #380-8811
San Francisco, CA 94115

You may also need to provide our email address: If you need other information for your grant, such as a contact person's name and phone number, email us and we'll provide that for you.