Starbucks Corp. tomorrow will offer its first discount through a major daily deal operator.

Google Inc.’s  daily deal arm Google Offers tomorrow will send consumers in its 40 markets an offer of a $10 Starbucks Card eGift for $5. The coffee retailer says it expects to sell up to 1 million Card eGifts during the one-day promotion.

Google says it will donate $3 for each offer sold to the Opportunity Finance Network, up to $3 million. The Opportunity Finance Network is a group of private financial institutions focused on making affordable loans to low-income consumers and communities.

The funds Google plans to donate to the group will not be drawn from the revenue generated by the offer.

April Anderson, industry director, retail, at Google, will speak at the Internet Retailer Conference & Exhibition 2012 in June, in a session entitled, “Paid search strategies for the smaller merchant.”