As the Wikimedia Foundation was formed on June 20, 2003, it is now possible for money to be sent to the accounts of Wikimedia. Please note that Wikimedia has not yet received an official determination of its 501(c)(3) tax exempt status under United States federal law, so these donations may be considered taxable income for Wikimedia and may not be deductible from the donor's income under the tax rules. Rest assured that they will be used for Wikimedia projects, including Wikipedia.
British Pounds
Canadian Dollars
European Euros
Japanese Yen
United States Dollars
You can also send donations via snail-mail to the official public record address of the Wikimedia Foundation:
  Wikimedia Foundation Inc. 
  3911 Harrisburg St. NE 
  St. Petersburg, FL 33703 
  
Legal status
Under Florida law the official corporate address for the Wikimedia Foundation Inc. is St. Petersburg, Florida, see donation addresses above. Any donations (money, stuff, copyright assignments) can certainly be sent there. Please note that they may not be tax deductible depending on the Internal Revenue Service's determination of the tax exempt status of Wikimedia. However anyone who wants to make a donation can certainly do so since Wikimedia does exist as an official not-for-profit corporation; also note that even though Wikimedia may not have tax exempt recognition, under US Internal Revenue Code provisions if Wikimedia's first year income is projected to be under $5,000, it has an automatic exemption.