diff --git a/lib/TransactionBuilder.js b/lib/TransactionBuilder.js
index 40e544d..ce33313 100644
--- a/lib/TransactionBuilder.js
+++ b/lib/TransactionBuilder.js
@@ -112,6 +112,7 @@ function TransactionBuilder(opts) {
   if (opts.fee || opts.feeSat) {
     this.givenFeeSat = opts.fee ? opts.fee * util.COIN : opts.feeSat;
   }
+  if (opts.fee == 0 || opts.feeSat == 0) this.givenFeeSat = 0;
   this.remainderOut = opts.remainderOut;
   this.signhash = opts.signhash || Transaction.SIGHASH_ALL;
 
@@ -358,7 +359,7 @@ TransactionBuilder.prototype._setFeeAndRemainder = function(txobj) {
     /* based on https://en.bitcoin.it/wiki/Transaction_fees */
     maxSizeK = parseInt(size / 1000) + 1;
 
-    var feeSat = this.givenFeeSat ?
+    var feeSat = this.givenFeeSat || this.givenFeeSat == 0  ?
       this.givenFeeSat : maxSizeK * FEE_PER_1000B_SAT;
 
     var neededAmountSat = this.valueOutSat.add(feeSat);