diff --git a/info.go b/info.go
index fde2bc98e..b06dffdbe 100644
--- a/info.go
+++ b/info.go
@@ -409,6 +409,11 @@ func (t JSONTime) Time() time.Time {
 func (t *JSONTime) UnmarshalJSON(buf []byte) error {
 	s := bytes.Trim(buf, `"`)
 
+	if bytes.EqualFold(s, []byte("null")) {
+		*t = JSONTime(0)
+		return nil
+	}
+
 	v, err := strconv.Atoi(string(s))
 	if err != nil {
 		return err
diff --git a/info_test.go b/info_test.go
new file mode 100644
index 000000000..baf91d0b9
--- /dev/null
+++ b/info_test.go
@@ -0,0 +1,44 @@
+package slack
+
+import (
+	"testing"
+)
+
+func TestJSONTime_UnmarshalJSON(t *testing.T) {
+	type args struct {
+		buf []byte
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantTr  JSONTime
+		wantErr bool
+	}{
+		{
+			"acceptable int64 timestamp",
+			args{[]byte(`1643435556`)},
+			JSONTime(1643435556),
+			false,
+		},
+		{
+			"acceptable string timestamp",
+			args{[]byte(`"1643435556"`)},
+			JSONTime(1643435556),
+			false,
+		},
+		{
+			"null",
+			args{[]byte(`null`)},
+			JSONTime(0),
+			false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var tr JSONTime
+			if err := tr.UnmarshalJSON(tt.args.buf); (err != nil) != tt.wantErr {
+				t.Errorf("JSONTime.UnmarshalJSON() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}