effectivealtruism.org is made by the Centre for Effective Altruism, which is an Effective Ventures project. Effective Ventures Foundation (UK) (EV UK) is a charity in England and Wales (with registered charity number 1149828, registered company number 07962181, and is also a Netherlands registered tax-deductible entity ANBI 825776867). Effective Ventures Foundation USA Inc. (EV US) is a section 501(c)(3) organization in the USA (EIN 47-1988398). EV UK and EV US are separate charities that collaborate closely under the “Effective Ventures” name.