WooCommerce sends transactional emails by default: order confirmation, shipping notice, password reset. But the real value lies in the automated flows you build on top.
Abandoned cart
70 percent of all carts are abandoned. Automated reminder emails can save 5 to 15 percent of them. First email after one hour ("You forgot something"), second after 24 hours (with product images), third after 72 hours (possibly with an incentive). Plugins: Retainful, AutomateWoo, or Mailchimp for WooCommerce.
Post-purchase flow
Three to seven days after delivery: ask if the product met expectations. Invite a review. Recommend related products. This flow costs nothing to send and drives repeat purchases.
Win-back
Customers who haven't purchased in 90 days: send a personal email. "We miss you" sounds silly, but a reminder that you exist with a relevant product recommendation works. Segment: customers who bought category X get emails about new items in category X.
Mailchimp or Klaviyo?
Mailchimp is easier to get started with and cheaper for low volume. The free plan covers 500 contacts. Klaviyo is more powerful: better segmentation, deeper WooCommerce integration, nicer automation builder. But it costs 20 USD per month starting at 250 contacts.
If you're just starting: Mailchimp. If you do more than 50,000 SEK in revenue per month: Klaviyo pays for itself.
All these flows are built once and then they run. Invest a day, earn money every day after that.