diff --git a/lib/nats/io/jetstream/pull_subscription.rb b/lib/nats/io/jetstream/pull_subscription.rb
index eb327ec..ef50eb7 100644
--- a/lib/nats/io/jetstream/pull_subscription.rb
+++ b/lib/nats/io/jetstream/pull_subscription.rb
@@ -55,7 +55,7 @@ def fetch(batch=1, params={})
         end
 
         t = MonotonicTime.now
-        timeout = params[:timeout] ||= 5
+        timeout = params[:timeout] ? Float(params[:timeout]) : 5.0
         expires = (timeout * 1_000_000_000) - 100_000
         next_req = {
           batch: batch