diff --git a/botsfwmodels/chat_base_data.go b/botsfwmodels/chat_base_data.go
index 79c11d9..32ce9ec 100644
--- a/botsfwmodels/chat_base_data.go
+++ b/botsfwmodels/chat_base_data.go
@@ -24,6 +24,7 @@ type ChatBaseData struct {
 	BotBaseData
 	chatState
 	chatSettings
+	chatVars
 
 	// AppUserIntIDs is kept for legacy reasons
 	// Deprecated: replace with `AppUserIDs []string`
diff --git a/botsfwmodels/chat_data.go b/botsfwmodels/chat_data.go
index d7c4071..c48d162 100644
--- a/botsfwmodels/chat_data.go
+++ b/botsfwmodels/chat_data.go
@@ -86,6 +86,11 @@ type BotChatData interface {
 	// PushStepToAwaitingReplyTo pushes step to awaiting reply to
 	PushStepToAwaitingReplyTo(code string)
 	//GetGaClientID() string
+
+	SetVar(key string, value string)
+	GetVar(key string) string
+	DelVar(key string)
+	HasChangedVars() bool
 }
 
 // NewChatID create a new bot chat ID, returns string
diff --git a/botsfwmodels/chat_vars.go b/botsfwmodels/chat_vars.go
new file mode 100644
index 0000000..c41744d
--- /dev/null
+++ b/botsfwmodels/chat_vars.go
@@ -0,0 +1,54 @@
+package botsfwmodels
+
+import (
+	"github.com/strongo/slice"
+	"slices"
+)
+
+type chatVars struct {
+	Vars    map[string]string `dalgo:"vars,omitempty" firestore:"vars,omitempty"`
+	changed []string
+	deleted []string
+}
+
+// GetVar returns a chat variable
+func (v *chatVars) GetVar(key string) string {
+	if v.Vars == nil {
+		return ""
+	}
+	return v.Vars[key]
+}
+
+// SetVar sets a chat variable
+func (v *chatVars) SetVar(key, value string) {
+	if v.Vars == nil {
+		v.Vars = make(map[string]string)
+	} else if v.Vars[key] == value {
+		return
+	}
+	v.Vars[key] = value
+	slice.RemoveInPlaceByValue(v.deleted, key)
+	if !slices.Contains(v.changed, key) {
+		v.changed = append(v.changed, key)
+	}
+}
+
+// DelVar deletes a chat variable
+func (v *chatVars) DelVar(key string) {
+	if v.Vars == nil {
+		return
+	}
+	if _, ok := v.Vars[key]; !ok {
+		return
+	}
+	delete(v.Vars, key)
+	v.changed = slice.RemoveInPlaceByValue(v.changed, key)
+	if !slices.Contains(v.deleted, key) {
+		v.deleted = append(v.deleted, key)
+	}
+}
+
+// HasChangedVars returns true if vars have been changed
+func (v *chatVars) HasChangedVars() bool {
+	return len(v.changed) > 0 || len(v.deleted) > 0
+}
diff --git a/go.mod b/go.mod
index dc49315..3d42874 100644
--- a/go.mod
+++ b/go.mod
@@ -3,3 +3,5 @@ module github.com/bots-go-framework/bots-fw-store
 go 1.22
 
 require github.com/strongo/validation v0.0.7
+
+require github.com/strongo/slice v0.3.1 // indirect
diff --git a/go.sum b/go.sum
index 26aab83..7d07123 100644
--- a/go.sum
+++ b/go.sum
@@ -1,2 +1,4 @@
+github.com/strongo/slice v0.3.1 h1:VWkyYBgcVJn6Hs7wYhL9Vxwgb7V3zQAUFTBV9wo5lc4=
+github.com/strongo/slice v0.3.1/go.mod h1:B5ODKCkl0rp2oiG0UBqkN1cCOrSCU2cUuhqCM1sC8r4=
 github.com/strongo/validation v0.0.7 h1:gs6YkwPsYtVsepQaQOB+ZF+T0Gu5+nk4ZMND8F85e+U=
 github.com/strongo/validation v0.0.7/go.mod h1:YUwoPEItLJd/Bc9X1OCUm03ofhvm3kwZvuihU7/jz58=