Replenishment emails are email notifications sent to your customers to remind them to reorder.
Which products
They are a best used for products that get used up or consumed by your customers. Common types include food (human, pet, wildlife), vitamins, and household consumables. Products with a longer lifecycle can also use replenishment emails like plant seeds, filters, clothing, or auto parts.
More general products or one-time purchase products should use a more general order reminder based on the order date and the Average Customer Purchase Latency.
Timing replenishment emails
Timing when to use a replenishment email should be product specific. If your product has a specific supply (e.g. 60-day supply of vitamins) then you'll want to use that as your base timing. It's best to notify them before they run out, either one or two weeks is sufficient for most shipping speeds.
A more advanced timing can use the Average Customer Purchase Latency but you'll want to have that to be measured per-product.
Formats other than email
Though primarily sent through email, other formats can be used to send these notifications. I've received them via text message (SMS) and some stores will find success using social media direct messages. Even a phone call can work for some stores, especially on higher priced products.
Email consent
Giving your customer the chance to consent to these notifications after checkout can be the most respectful option. Depending on your emailing tool you might even be able to let them pick the frequency of contact.
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