diff --git a/packages/providers/src.ts/formatter.ts b/packages/providers/src.ts/formatter.ts
index 1810825a41..c7cf69f80a 100644
--- a/packages/providers/src.ts/formatter.ts
+++ b/packages/providers/src.ts/formatter.ts
@@ -328,28 +328,39 @@ export class Formatter {
         }
         */
 
-        let result = Formatter.check(this.formats.transaction, transaction);
+        let result: TransactionResponse = Formatter.check(this.formats.transaction, transaction);
 
-        let networkId = transaction.networkId;
+        if (transaction.chainId != null) {
+            let chainId = transaction.chainId;
 
-        // geth-etc returns chainId
-        if (transaction.chainId != null && networkId == null && result.v == null) {
-            networkId = transaction.chainId;
-        }
+            if (isHexString(chainId)) {
+                chainId = BigNumber.from(chainId).toNumber();
+            }
 
-        if (isHexString(networkId)) {
-            networkId = BigNumber.from(networkId).toNumber();
-        }
+            result.chainId = chainId;
 
-        if (typeof(networkId) !== "number" && result.v != null) {
-            networkId = (result.v - 35) / 2;
-            if (networkId < 0) { networkId = 0; }
-            networkId = parseInt(networkId);
-        }
+        } else {
+            let chainId = transaction.networkId;
 
-        if (typeof(networkId) !== "number") { networkId = 0; }
+            // geth-etc returns chainId
+            if (chainId == null && result.v == null) {
+                chainId = transaction.chainId;
+            }
 
-        result.networkId = networkId;
+            if (isHexString(chainId)) {
+                chainId = BigNumber.from(chainId).toNumber();
+            }
+
+            if (typeof(chainId) !== "number" && result.v != null) {
+                chainId = (result.v - 35) / 2;
+                if (chainId < 0) { chainId = 0; }
+                chainId = parseInt(chainId);
+            }
+
+            if (typeof(chainId) !== "number") { chainId = 0; }
+
+            result.chainId = chainId;
+        }
 
         // 0x0000... should actually be null
         if (result.blockHash && result.blockHash.replace(/0/g, "") === "x") {