Your Store account name or Store ID can be found on your Account Info page.

To find your Store Account Name (ID):

1. Sign in to your account.
2. Go to the Store Manager.
3. Click the "Account Info" link under the Site Settings column.
4. At the top of the page you will see "Store Account Name" (see figure 1). The account name will be the automatically generated identifier assigned to your store when you signed up, beginning with the letters "yhst-" (for example yhst-12345678910112). When copying the account name (ID), the "yhst" must be included.
   Merchants who signed up for their store with Yahoo! Stores (prior to the Yahoo! Merchant Solutions offering) may have chosen an ID for their store at the time of signup (for example, acmestore).
   
   Note: Most merchants will have an automatically generated ID beginning with "yhst." You are not able to rename your store ID.

Figure 1: Account Info page with Store Account Name (ID) highlighted