I run an ecommerce dog treat company, and I typically send out about one email a week. I try to keep those to 50% or less emails that offer discounts, and I try

I run an ecommerce dog treat company, and I typically send out about one email a week. I try to keep those to 50% or less emails that offer discounts, and I try to make the discounts product-specific, so people don't just get used to getting a 20% off coupon twice a month. For the non-discount emails, I'll just send something about the company or the products. If I was on a morning show talking about the company, I'll send out the video. If I don't have anything else out, I just remind people of the fact that it's very hot, and we sell frozen dog treat mix. Each email goes out to about 3500 people and generates 3-15 sales. Discount emails do better than non-discount, but some non-discount (like good press coverage) do very well. New product launches and sales for major holidays when people are looking to shop (e.g. Memorial Day, BFCM) do over 15 sales. I've tested doing it less often, and ultimately doing one email a week barely affects unsubscribes and easily generates enough extra revenue to be worth it.