diff --git a/signup_test.go b/signup_test.go
index 05609a1..978903d 100644
--- a/signup_test.go
+++ b/signup_test.go
@@ -749,7 +749,7 @@ func TestSnapMail(t *testing.T) {
 			StartDateTime: mustMakeTime(t, time.RFC3339, "2023-09-23T18:00:00.000Z"),
 			Cell:          "555-555-5555",
 		}
-		wantJSON := `{"eventType":"SESSION_SIGNUP","payload":{"email":"abigailtest@test.org","nameFirst":"Abigail","nameLast":"Test","sessionId":"tMisBjpLQt8H3oD8B","startDateTime":"2023-09-23T18:00:00Z","phone":"555-555-5555"}}`
+		wantJSON := `{"eventType":"SESSION_SIGNUP","payload":{"email":"abigailtest@test.org","nameFirst":"Abigail","nameLast":"Test","sessionId":"tMisBjpLQt8H3oD8B","startDateTime":"2023-09-23T18:00:00Z","mobile":"555-555-5555"}}`
 
 		mockSnapServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			assertEqual(t, r.URL.Path, "/events")
diff --git a/snapmail.go b/snapmail.go
index eab5d7b..70393c5 100644
--- a/snapmail.go
+++ b/snapmail.go
@@ -22,7 +22,7 @@ type Payload struct {
 	NameLast      string    `json:"nameLast"`
 	SessionID     string    `json:"sessionId"`
 	StartDateTime time.Time `json:"startDateTime,omitempty"`
-	Phone         string    `json:"phone"`
+	Mobile        string    `json:"mobile"`
 }
 
 type signupEvent struct {
@@ -66,7 +66,7 @@ func (sm *SnapMail) run(ctx context.Context, signup Signup) error {
 			NameLast:      signup.NameLast,
 			SessionID:     signup.SessionID,
 			StartDateTime: signup.StartDateTime,
-			Phone:         signup.Cell,
+			Mobile:        signup.Cell,
 		},
 	}