diff --git a/lib/errors/spec.js b/lib/errors/spec.js
index c7adece..03eabc4 100644
--- a/lib/errors/spec.js
+++ b/lib/errors/spec.js
@@ -85,14 +85,18 @@ module.exports = [{
     name: 'InvalidSatoshis',
     message: 'Output satoshis are invalid',
   }, {
-    name: 'SmallFeeError',
-    message: 'Fee is too small: {0}',
-  }, {
-    name: 'LargeFeeError',
-    message: 'Fee is too large: {0}',
-  }, {
-    name: 'DifferentFeeError',
-    message: 'Unspent value is different from specified fee: {0}',
+    name: 'Fee',
+    message: 'Internal Error on Fee {0}',
+    errors: [{
+      name: 'TooSmallError',
+      message: 'Fee is too small: {0}',
+    }, {
+      name: 'TooLargeError',
+      message: 'Fee is too large: {0}',
+    }, {
+      name: 'DifferentError',
+      message: 'Unspent value is different from specified fee: {0}',
+    }]
   }, {
     name: 'ChangeAddressMissing',
     message: 'Change address is missing'
diff --git a/lib/transaction/transaction.js b/lib/transaction/transaction.js
index 8729557..9890cf9 100644
--- a/lib/transaction/transaction.js
+++ b/lib/transaction/transaction.js
@@ -203,16 +203,16 @@ Transaction.prototype.getSerializationError = function(opts) {
   var isFullySigned = this.isFullySigned();
 
   if (!opts.disableDifferentFees && feeIsDifferent) {
-    return new errors.Transaction.DifferentFeeError(feeIsDifferent);
+    return new errors.Transaction.Fee.DifferentError(feeIsDifferent);
   }
   if (!opts.disableLargeFees && feeIsTooLarge) {
     if (missingChange) {
       return new errors.Transaction.ChangeAddressMissing('Fee is too large and no change address was provided');
     }
-    return new errors.Transaction.LargeFeeError(feeIsTooLarge);
+    return new errors.Transaction.Fee.TooLargeError(feeIsTooLarge);
   }
   if (!opts.disableSmallFees && feeIsTooSmall) {
-    return new errors.Transaction.SmallFeeError(feeIsTooSmall);
+    return new errors.Transaction.Fee.TooSmallError(feeIsTooSmall);
   }
   if (!opts.disableDustOutputs && this._hasDustOutputs()) {
     return new errors.Transaction.DustOutputs();
diff --git a/test/transaction/transaction.js b/test/transaction/transaction.js
index cf8ff21..18c8e71 100644
--- a/test/transaction/transaction.js
+++ b/test/transaction/transaction.js
@@ -266,7 +266,7 @@ describe('Transaction', function() {
         .sign(privateKey);
       expect(function() {
         return transaction.serialize();
-      }).to.throw(errors.Transaction.SmallFeeError);
+      }).to.throw(errors.Transaction.Fee.TooSmallError);
     });
     it('on second call to sign, change is not recalculated', function() {
       var transaction = new Transaction()
@@ -332,7 +332,7 @@ describe('Transaction', function() {
         .to(toAddress, 40000000);
       expect(function() {
         return transaction.serialize();
-      }).to.throw(errors.Transaction.LargeFeeError);
+      }).to.throw(errors.Transaction.Fee.TooLargeError);
     });
     it('fails if a dust output is created', function() {
       var transaction = new Transaction()
@@ -372,7 +372,7 @@ describe('Transaction', function() {
         .sign(privateKey);
       expect(function() {
         return transaction.serialize();
-      }).to.throw(errors.Transaction.DifferentFeeError);
+      }).to.throw(errors.Transaction.Fee.DifferentError);
     });
     describe('skipping checks', function() {
       var buildSkipTest = function(builder, check) {