diff --git a/lib/mempool/fees.js b/lib/mempool/fees.js
index ef1482ce..4b29ab17 100644
--- a/lib/mempool/fees.js
+++ b/lib/mempool/fees.js
@@ -697,6 +697,9 @@ PolicyEstimator.prototype.estimateFee = function estimateFee(target, smart) {
   if (rate < this.network.feeRate)
     return this.network.feeRate;
 
+  if (rate > this.network.maxFeeRate)
+    return this.network.maxFeeRate;
+
   if (rate < 0)
     return 0;
 
diff --git a/lib/protocol/network.js b/lib/protocol/network.js
index 46363e3c..4144937d 100644
--- a/lib/protocol/network.js
+++ b/lib/protocol/network.js
@@ -46,6 +46,7 @@ function Network(options) {
   this.rpcPort = options.rpcPort;
   this.minRelay = options.minRelay;
   this.feeRate = options.feeRate;
+  this.maxFeeRate = options.maxFeeRate;
   this.selfConnect = options.selfConnect;
   this.requestMempool = options.requestMempool;
   this.batchSize = options.batchSize;
diff --git a/lib/protocol/networks.js b/lib/protocol/networks.js
index 1796d338..7c75f176 100644
--- a/lib/protocol/networks.js
+++ b/lib/protocol/networks.js
@@ -419,6 +419,14 @@ main.minRelay = 10000;
 
 main.feeRate = 50000;
 
+/**
+ * Maximum normal relay rate.
+ * @const {Rate}
+ * @default
+ */
+
+main.maxFeeRate = 150000;
+
 /**
  * Whether to allow self-connection.
  * @const {Boolean}
@@ -603,6 +611,8 @@ testnet.minRelay = 10000;
 
 testnet.feeRate = 20000;
 
+testnet.maxFeeRate = 60000;
+
 testnet.selfConnect = false;
 
 testnet.requestMempool = false;
@@ -748,6 +758,8 @@ regtest.minRelay = 10000;
 
 regtest.feeRate = 20000;
 
+regtest.maxFeeRate = 60000;
+
 regtest.selfConnect = true;
 
 regtest.requestMempool = true;
@@ -869,6 +881,8 @@ segnet3.minRelay = 10000;
 
 segnet3.feeRate = 20000;
 
+segnet3.maxFeeRate = 60000;
+
 segnet3.selfConnect = false;
 
 segnet3.requestMempool = true;
@@ -1007,6 +1021,8 @@ segnet4.minRelay = 10000;
 
 segnet4.feeRate = 20000;
 
+segnet4.maxFeeRate = 60000;
+
 segnet4.selfConnect = false;
 
 segnet4.requestMempool = true;
@@ -1153,6 +1169,8 @@ simnet.minRelay = 10000;
 
 simnet.feeRate = 20000;
 
+simnet.maxFeeRate = 60000;
+
 simnet.selfConnect = true;
 
 simnet.requestMempool = false;