diff --git a/lib/http/server.js b/lib/http/server.js
index 1b72ee89..fa702f67 100644
--- a/lib/http/server.js
+++ b/lib/http/server.js
@@ -271,8 +271,8 @@ HTTPServer.prototype._init = function _init() {
         options.subtractFee = params.subtractFee;
         assert(utils.isUInt32(options.subtractFee), 'subtractFee must be a number.');
       } else {
-        assert(typeof options.subtractFee === 'boolean', 'subtractFee must be a boolean.');
         options.subtractFee = params.subtractFee;
+        assert(typeof options.subtractFee === 'boolean', 'subtractFee must be a boolean.');
       }
     }