Wineries are often asked to donate bottles of wine or other products for charitable causes. Goods donated to nonprofits without any intervening use are not subject to retailing B&O tax or sales tax (since they are given away without a charge). The donor (winery) also does not owe use tax on the value of the wine.
Note: You must keep documentation supporting the donation in your records.
RCW 82.12.02595 Personal property and certain services donated to nonprofit organizations or governmental entities.