diff --git a/src/Transaction.js b/src/Transaction.js
index 1e9acde..de80468 100644
--- a/src/Transaction.js
+++ b/src/Transaction.js
@@ -465,7 +465,7 @@ class Transaction {
     const block = await this._provider.getBlock('latest')
 
     // Check network support for EIP-1559
-    if (block && block.baseFeePerGas) {
+    if (this.config.ENABLE_EIP1559 && block && block.baseFeePerGas) {
       const maxPriorityFeePerGas = await this._estimatePriorityFee(block.number)
 
       const maxFeePerGas = block.baseFeePerGas
diff --git a/src/TxManager.js b/src/TxManager.js
index 29bdb4b..18d143a 100644
--- a/src/TxManager.js
+++ b/src/TxManager.js
@@ -15,6 +15,7 @@ const defaultConfig = {
   ESTIMATE_GAS: true,
   THROW_ON_REVERT: true,
   BLOCK_GAS_LIMIT: null,
+  ENABLE_EIP1559: true,
   PRIORITY_FEE_GWEI: 3,
   BASE_FEE_RESERVE_PERCENTAGE: 50,
 }
diff --git a/test/TxManager.test.js b/test/TxManager.test.js
index 28afd4f..44a3c0e 100644
--- a/test/TxManager.test.js
+++ b/test/TxManager.test.js
@@ -1,19 +1,13 @@
 require('dotenv').config()
 require('chai').should()
+const { providers } = require('ethers')
 const { parseUnits } = require('ethers').utils
 const TxManager = require('../src/TxManager')
 // const Transaction = require('../src/Transaction')
 const { RPC_URL, PRIVATE_KEY } = process.env
 
 describe('TxManager', () => {
-  const manager = new TxManager({
-    privateKey: PRIVATE_KEY,
-    rpcUrl: RPC_URL,
-    config: {
-      CONFIRMATIONS: 1,
-      GAS_BUMP_INTERVAL: 1000 * 20,
-    },
-  })
+  let manager
 
   const tx1 = {
     value: 1,
@@ -45,6 +39,26 @@ describe('TxManager', () => {
     type: 2,
   }
 
+  before(async () => {
+    const provider = new providers.JsonRpcProvider(RPC_URL)
+
+    const { name, chainId } = await provider.getNetwork()
+    console.log('\n\n', 'network', { name, chainId }, '\n\n')
+
+    manager = new TxManager({
+      privateKey: PRIVATE_KEY,
+      rpcUrl: RPC_URL,
+      config: {
+        CONFIRMATIONS: 1,
+        GAS_BUMP_INTERVAL: 1000 * 20,
+      },
+      gasPriceOracleConfig: {
+        chainId: chainId,
+        defaultRpc: RPC_URL,
+      },
+    })
+  })
+
   describe('#transaction', () => {
     it('should work legacy tx', async () => {
       const tx = manager.createTx(tx1)
@@ -138,6 +152,20 @@ describe('TxManager', () => {
       console.log('receipt', receipt)
     })
 
+    it('should disable eip-1559 transactions', async () => {
+      manager.config.ENABLE_EIP1559 = false
+
+      const tx = manager.createTx(tx3)
+      const receipt = await tx
+        .send()
+        .on('transactionHash', hash => console.log('hash', hash))
+        .on('mined', receipt => console.log('Mined in block', receipt.blockNumber))
+        .on('confirmations', confirmations => console.log('confirmations', confirmations))
+      console.log('receipt', receipt)
+
+      manager.config.ENABLE_EIP1559 = true
+    })
+
     it('should send multiple txs', async () => {
       const genTx = value => ({
         value,