Stop maintaining recipient lists by hand: dynamic contact groups always contain exactly the contacts that match your rules, from "birthday today" to "no reply in 30 days".

Dynamic contact groups
Define the rule once, the list keeps itself up to date. When you create a group, choose "Dynamic" instead of "Static": from then on the group contains every contact that matches your conditions.
Filter by what you know about your contacts
- Contact fields - name, birthday, validation date and more
- Your custom fields - whatever you store for your contacts
- Group membership - for example "member of VIP"
- Communication - last messaged, last reply received, number of sent and received messages, last channel
Date fields also work relative: "in the last 30 days", "anniversary is today" or "anniversary in the next 7 days" - perfect for birthday SMS.
Combine conditions your way
- All conditions within a block must match (AND)
- Several blocks widen the group (OR)
- The live preview shows how many contacts match before you save
Works wherever you send
- Members are recalculated right before every send, so nobody is missing and nobody is too many
- In the dashboard, in recurring sends, via Email2SMS and in the REST API with the group name as recipient (Docs)
- The conditions decide who is in: members can't be added or removed by hand
New on every contact
The contact details and the preview panel show when you last messaged a contact, when they last replied, how many messages were sent and received and which channel was used last. Your past conversations are already included.