diff --git a/android/src/main/kotlin/africa/ejara/trustdart/Coin.kt b/android/src/main/kotlin/africa/ejara/trustdart/Coin.kt
index 7490432..f8f5b17 100644
--- a/android/src/main/kotlin/africa/ejara/trustdart/Coin.kt
+++ b/android/src/main/kotlin/africa/ejara/trustdart/Coin.kt
@@ -4,6 +4,7 @@ import africa.ejara.trustdart.interfaces.CoinInterface
 import africa.ejara.trustdart.utils.base64String
 import africa.ejara.trustdart.utils.toHex
 import africa.ejara.trustdart.utils.toHexByteArray
+import com.google.protobuf.ByteString
 import org.json.JSONObject
 import wallet.core.java.AnySigner
 import wallet.core.jni.CoinType
@@ -43,13 +44,13 @@ open class Coin(nameOfCoin: String, typeOfCoin: CoinType) : CoinInterface {
     override fun getRawPrivateKey(path: String, mnemonic: String, passphrase: String): ByteArray? {
         val wallet = HDWallet(mnemonic, passphrase)
         return wallet.getKey(coinType, path).data()
-    }
+    } 
 
     override fun getPublicKey(path: String, mnemonic: String, passphrase: String): String? {
         val wallet = HDWallet(mnemonic, passphrase)
         return wallet.getKey(coinType, path).getPublicKeySecp256k1(true).data().base64String()
     }
-
+ 
     override fun getRawPublicKey(path: String, mnemonic: String, passphrase: String): ByteArray? {
         val wallet = HDWallet(mnemonic, passphrase)
         return wallet.getKey(coinType, path).getPublicKeySecp256k1(true).data()
@@ -82,4 +83,18 @@ open class Coin(nameOfCoin: String, typeOfCoin: CoinType) : CoinInterface {
         return AnySigner.signJSON(opJson, privateKey.data(), coinType!!.value())
     }
 
+    override fun multiSignTransaction(
+        txData: Map<String, Any>,
+        privateKeys: ArrayList<String>
+    ): String? {
+        val opJson = JSONObject(txData).toString()
+        val signatures = mutableListOf<String>()
+
+        for (privateKey in privateKeys) {
+            val signature = AnySigner.signJSON(opJson, privateKey.toByteArray(), coinType!!.value())
+            signatures.add(signature)
+        }
+        return signatures.joinToString(",")
+    }
+
 }
diff --git a/android/src/main/kotlin/africa/ejara/trustdart/TrustdartPlugin.kt b/android/src/main/kotlin/africa/ejara/trustdart/TrustdartPlugin.kt
index 36b3795..f9984c6 100644
--- a/android/src/main/kotlin/africa/ejara/trustdart/TrustdartPlugin.kt
+++ b/android/src/main/kotlin/africa/ejara/trustdart/TrustdartPlugin.kt
@@ -56,7 +56,7 @@ class TrustdartPlugin : FlutterPlugin, MethodCallHandler {
                     validator.details.errorMessage,
                     validator.details.errorDetails
                 )
-            }
+            } 
             "checkMnemonic" -> {
                 val mnemonic: String? = call.argument("mnemonic")
                 val passphrase: String? = call.argument("passphrase")
@@ -164,6 +164,35 @@ class TrustdartPlugin : FlutterPlugin, MethodCallHandler {
                     validator.details.errorDetails
                 )
             }
+            "multiSignTransaction" -> {
+                val coin: String? = call.argument("coin")
+                val txData: Map<String, Any>? = call.argument("txData")
+                val privateKeys: ArrayList<String>? = call.argument("privateKeys")
+                var validator = WalletHandler().validate(
+                    WalletError(
+                        WalletHandlerErrorCodes.ArgumentsNull,
+                        "[coin], [privateKeys] and [txData] are required.",
+                        null
+                    ), arrayOf(coin, txData, privateKeys)
+                )
+                if (validator.isValid) {
+                    val txHash = WalletHandler().getCoin(coin)
+                        .multiSignTransaction(txData!!, privateKeys!!)
+                    validator = WalletHandler().validate(
+                        WalletError(
+                            WalletHandlerErrorCodes.TxHashNull,
+                            "Could not sign transaction.",
+                            null
+                        ), arrayOf(txHash)
+                    )
+                    if (validator.isValid) return result.success(txHash)
+                }
+                return result.error(
+                    validator.details.errorCode,
+                    validator.details.errorMessage,
+                    validator.details.errorDetails
+                )
+            }
             "signDataWithPrivateKey" -> {
                 val coin: String? = call.argument("coin")
                 val path: String? = call.argument("path")
diff --git a/android/src/main/kotlin/africa/ejara/trustdart/coins/BTC.kt b/android/src/main/kotlin/africa/ejara/trustdart/coins/BTC.kt
index 3825345..3c35715 100644
--- a/android/src/main/kotlin/africa/ejara/trustdart/coins/BTC.kt
+++ b/android/src/main/kotlin/africa/ejara/trustdart/coins/BTC.kt
@@ -1,5 +1,6 @@
 import africa.ejara.trustdart.Coin
 import africa.ejara.trustdart.Numeric
+import africa.ejara.trustdart.utils.toHex
 import africa.ejara.trustdart.utils.toLong
 import com.google.protobuf.ByteString
 import wallet.core.java.AnySigner
@@ -9,6 +10,8 @@ import wallet.core.jni.CoinType
 import wallet.core.jni.HDWallet
 import wallet.core.jni.proto.Bitcoin
 
+ 
+
 
 class BTC : Coin("BTC", CoinType.BITCOIN) {
 
@@ -77,4 +80,56 @@ class BTC : Coin("BTC", CoinType.BITCOIN) {
         return Numeric.toHexString(output.encoded.toByteArray())
     }
 
-}
\ No newline at end of file
+
+    override fun multiSignTransaction(
+        txData: Map<String, Any>,
+        privateKeys: ArrayList<String>
+    ): String? {
+        val utxos: List<Map<String, Any>> = txData["utxos"] as List<Map<String, Any>>
+
+        val input = Bitcoin.SigningInput.newBuilder()
+            .setAmount(txData["amount"]!!.toLong())
+            .setHashType(BitcoinScript.hashTypeForCoin(coinType))
+            .setToAddress(txData["toAddress"] as String)
+            .setChangeAddress(txData["changeAddress"] as String)
+            .setByteFee(1)
+
+        val byteStrings: MutableList<ByteString> = privateKeys.map { ByteString.copyFrom(Numeric.hexStringToByteArray(it)) }.toMutableList()
+
+        input.addAllPrivateKey(byteStrings);
+
+        for (utx in utxos) {
+            val txHash = Numeric.hexStringToByteArray(utx["txid"] as String)
+            txHash.reverse()
+            val outPoint = Bitcoin.OutPoint.newBuilder()
+                .setHash(ByteString.copyFrom(txHash))
+                .setIndex(utx["vout"] as Int)
+                .setSequence(Long.MAX_VALUE.toInt())
+                .build()
+            val txScript = Numeric.hexStringToByteArray(utx["script"] as String)
+            val utxo = Bitcoin.UnspentTransaction.newBuilder()
+                .setAmount(utx["value"]!!.toLong())
+                .setOutPoint(outPoint)
+                .setScript(ByteString.copyFrom(txScript))
+                .build()
+            input.addUtxo(utxo)
+        }
+
+        var output = AnySigner.sign(input.build(), coinType, Bitcoin.SigningOutput.parser())
+
+        // since we want to set our own fee
+        // but such functionality is not obvious in the trustwalletcore library
+        // a hack is used for now to calculate the byteFee
+        val size = output.encoded.toByteArray().size
+        val fees = txData["fees"]!!.toLong()
+        if (size > 0) { // prevent division by zero
+            val byteFee = fees.div(size) // this gives the fee per byte truncated to Long
+            // now we set new byte size
+            if (byteFee > 1) input.byteFee = byteFee
+        }
+        output = AnySigner.sign(input.build(), coinType, Bitcoin.SigningOutput.parser())
+        return Numeric.toHexString(output.encoded.toByteArray())
+    }
+
+};
+           
\ No newline at end of file
diff --git a/android/src/main/kotlin/africa/ejara/trustdart/coins/XTZ.kt b/android/src/main/kotlin/africa/ejara/trustdart/coins/XTZ.kt
index 07de6bd..669ef35 100644
--- a/android/src/main/kotlin/africa/ejara/trustdart/coins/XTZ.kt
+++ b/android/src/main/kotlin/africa/ejara/trustdart/coins/XTZ.kt
@@ -4,7 +4,6 @@ import africa.ejara.trustdart.utils.base64String
 import africa.ejara.trustdart.utils.toHex
 import africa.ejara.trustdart.utils.toHexBytes
 import africa.ejara.trustdart.utils.toLong
-import android.util.Log
 import com.google.protobuf.ByteString
 import org.json.JSONObject
 import wallet.core.java.AnySigner
diff --git a/android/src/main/kotlin/africa/ejara/trustdart/interfaces/CoinInterface.kt b/android/src/main/kotlin/africa/ejara/trustdart/interfaces/CoinInterface.kt
index 752a20c..a7e556b 100644
--- a/android/src/main/kotlin/africa/ejara/trustdart/interfaces/CoinInterface.kt
+++ b/android/src/main/kotlin/africa/ejara/trustdart/interfaces/CoinInterface.kt
@@ -1,4 +1,6 @@
 package africa.ejara.trustdart.interfaces
+ 
+import com.google.protobuf.ByteString
 
 interface CoinInterface {
     fun generateAddress(path: String, mnemonic: String, passphrase: String): Map<String, String>?
@@ -10,4 +12,8 @@ interface CoinInterface {
     fun validateAddress(address: String): Boolean
     fun signDataWithPrivateKey(path: String, mnemonic: String, passphrase: String, txData: String): String?
     fun signTransaction(path: String, txData: Map<String, Any>, mnemonic: String, passphrase: String): String?
+   fun multiSignTransaction(
+       txData: Map<String, Any>,
+       privateKeys: ArrayList<String>
+   ): String?
 }
\ No newline at end of file
diff --git a/example/lib/operations.dart b/example/lib/operations.dart
index b27fd15..08fb7df 100644
--- a/example/lib/operations.dart
+++ b/example/lib/operations.dart
@@ -102,7 +102,13 @@ Map<String, dynamic> operations = {
     "amount": 3000,
     "fees": 1000,
     "changeAddress": "15o5bzVX58t1NRvLchBUGuHscCs1sumr2R",
-    "change": 500
+    "change": 500,
+    "privateKeys": [
+      "a321c4996143e0add05864bbb694ceb399fbe5d0884d721b1a04755f9f7497a9",
+      "bbc27228ddcb9209d7fd6f36b02f7dfa6252af40bb2f1cbc7a557da8027ff866",
+      "619c335025c7f4012e556c2a58b2506e30b8511b53ade95ea316fd8c3286feb9",
+      "eae04f225475e7630e58efdbefe50a003efd7e2ade3e67e171e023e9278b6ea4"
+    ]
   },
   'TRX': {
     "cmd": "TRC20", // can be TRC20 | TRX | TRC10 | CONTRACT | FREEZE
@@ -320,6 +326,12 @@ runOperations() async {
       print('Transaction Check ...');
       print([tx]);
 
+      print(operations[coin.code]["privateKeys"]);
+      String multiTxSign = await Trustdart.multiSignTransaction(coin.code,
+          operations[coin.code], operations[coin.code]["privateKeys"]);
+      print('MultiSig Transaction Check ...');
+      print([multiTxSign]);
+
       String signedData = (await Trustdart.signDataWithPrivateKey(
         dondo,
         coin.code,
diff --git a/ios/Classes/Coin.swift b/ios/Classes/Coin.swift
index bfe1874..5ed68c5 100644
--- a/ios/Classes/Coin.swift
+++ b/ios/Classes/Coin.swift
@@ -15,7 +15,7 @@ class Coin: CoinProtocol {
     init(name: String, coinType: CoinType){
         self.name = name
         self.coinType = coinType
-    }
+    } 
     
     func getName() -> String {
         return self.name
@@ -79,4 +79,21 @@ class Coin: CoinProtocol {
         }
         return nil
     }
+
+
+
+    func multiSignTransaction(txData: [String: Any], privateKeys: [String]) -> String? {
+        let opJson =  Utils.objToJson(from: txData)
+        var signatures = [String]()
+        
+        for privateKey in privateKeys {
+            let signature = AnySigner.signJSON(opJson!, key: privateKey.data(using: .utf8)!, coin: self.coinType)
+            signatures.append(signature)
+        }
+        if signatures.isEmpty {
+            return nil
+        } else {
+            return signatures.joined(separator: ",")
+        }
+}
 }
diff --git a/ios/Classes/SwiftTrustdartPlugin.swift b/ios/Classes/SwiftTrustdartPlugin.swift
index e803fa4..b6d71d8 100644
--- a/ios/Classes/SwiftTrustdartPlugin.swift
+++ b/ios/Classes/SwiftTrustdartPlugin.swift
@@ -15,7 +15,7 @@ public class SwiftTrustdartPlugin: NSObject, FlutterPlugin {
             let wallet = WalletHandler().generateMnemonic(strength: 128, passphrase: call.arguments as! String)
             let (isValid, err) = WalletHandler.validate(walletError: WalletError(code: .noWallet, message: "Could not generate wallet", details: nil), wallet)
             if isValid {
-                result(wallet)
+                result(wallet) 
             }else {
                 result(err.details)
             }
@@ -72,6 +72,26 @@ public class SwiftTrustdartPlugin: NSObject, FlutterPlugin {
             if isValid {
                 let txHash = WalletHandler().getCoin(coin!).signTransaction(path: path!, txData: txData!, mnemonic: mnemonic!, passphrase: passphrase!)
                 
+                let (isValid, err) = WalletHandler.validate(walletError: WalletError(code: .txHashNull, message: "Failed to sign transaction.", details: nil), txHash)
+                if isValid {
+                    result(txHash)
+                }else {
+                    result(err.details)
+                } 
+            }else {
+                result(err.details)
+            }
+            
+        case "multiSignTransaction":
+            let args = call.arguments as! [String: Any]
+            let coin: String? = args["coin"] as? String
+            let txData: [String: Any]? = args["txData"] as? [String: Any]
+            let privateKeys: [String]? = args["privateKeys"] as? [String]
+            let (isValid, err) = WalletHandler.validate(walletError: WalletError(code: .argumentsNull, message: "[coin] are required.", details: nil), coin)
+            
+            if isValid {
+                let txHash = WalletHandler().getCoin(coin!).multiSignTransaction(txData: txData!, privateKeys: privateKeys ?? [] )
+                
                 let (isValid, err) = WalletHandler.validate(walletError: WalletError(code: .txHashNull, message: "Failed to sign transaction.", details: nil), txHash)
                 if isValid {
                     result(txHash)
@@ -81,6 +101,7 @@ public class SwiftTrustdartPlugin: NSObject, FlutterPlugin {
             }else {
                 result(err.details)
             }
+
         case "signDataWithPrivateKey":
             let args = call.arguments as! [String: Any]
             let coin: String? = args["coin"] as? String
diff --git a/ios/Classes/coins/BTC.swift b/ios/Classes/coins/BTC.swift
index 6479c0a..86a0aa1 100644
--- a/ios/Classes/coins/BTC.swift
+++ b/ios/Classes/coins/BTC.swift
@@ -48,7 +48,7 @@ class BTC: Coin  {
                 $0.privateKey = [privateKey!.data]
                 $0.plan = BitcoinTransactionPlan.with {
                     $0.amount = txData["amount"] as! Int64
-                    $0.fee = txData["fees"] as! Int64
+                    $0.fee = txData["fees"] as! Int64 
                     $0.change = txData["change"] as! Int64
                     $0.utxos = unspent
                 }
@@ -61,4 +61,43 @@ class BTC: Coin  {
         }
         
     }
+
+
+    
+    override func multiSignTransaction(txData: [String : Any], privateKeys: [String]) -> String? {
+        let utxos: [[String: Any]] = txData["utxos"] as! [[String: Any]]
+        var unspent: [BitcoinUnspentTransaction] = []
+        
+            for utx in utxos {
+                unspent.append(BitcoinUnspentTransaction.with {
+                    $0.outPoint.hash = Data.reverse(hexString: utx["txid"] as! String)
+                    $0.outPoint.index = utx["vout"] as! UInt32
+                    $0.outPoint.sequence = UINT32_MAX
+                    $0.amount = utx["value"] as! Int64
+                    $0.script = Data(hexString: utx["script"] as! String)!
+                })
+            }
+            let privateKeyDataArray = privateKeys.compactMap { privateKey in
+                return Data(hexString: privateKey)
+            }
+
+            let input: BitcoinSigningInput = BitcoinSigningInput.with {
+                $0.hashType = BitcoinScript.hashTypeForCoin(coinType: .bitcoin)
+                $0.amount = txData["amount"] as! Int64
+                $0.toAddress = txData["toAddress"] as! String
+                $0.changeAddress = txData["changeAddress"] as! String // can be same sender address
+                $0.privateKey = privateKeyDataArray
+                $0.plan = BitcoinTransactionPlan.with {
+                    $0.amount = txData["amount"] as! Int64
+                    $0.fee = txData["fees"] as! Int64
+                    $0.change = txData["change"] as! Int64
+                    $0.utxos = unspent
+                }
+            }
+            
+            let output: BitcoinSigningOutput = AnySigner.sign(input: input, coin: .bitcoin)
+            return output.encoded.hexString
+        
+    }
+
 }
diff --git a/ios/Classes/protocols/CoinProtocol.swift b/ios/Classes/protocols/CoinProtocol.swift
index fb73e4e..9f08df2 100644
--- a/ios/Classes/protocols/CoinProtocol.swift
+++ b/ios/Classes/protocols/CoinProtocol.swift
@@ -18,4 +18,6 @@ protocol CoinProtocol {
     func validateAddress(address: String) -> Bool
     func signDataWithPrivateKey(path: String, mnemonic: String, passphrase: String, txData: String) -> String?
     func signTransaction(path: String, txData: [String: Any], mnemonic: String, passphrase: String) -> String?
+    func multiSignTransaction(txData: [String: Any], privateKeys: [String]) -> String?
+
 }
diff --git a/lib/trustdart.dart b/lib/trustdart.dart
index 0d224cd..5561c07 100644
--- a/lib/trustdart.dart
+++ b/lib/trustdart.dart
@@ -171,6 +171,21 @@ class Trustdart {
     }
   }
 
+  static Future<String> multiSignTransaction(
+      String coin, Map txData, List<String>? privateKeys) async {
+    try {
+      final String txHash = await _channel.invokeMethod(
+          'multiSignTransaction', <String, dynamic>{
+        'coin': coin,
+        'txData': txData,
+        'privateKeys': privateKeys
+      });
+      return txHash;
+    } catch (e) {
+      return '';
+    }
+  }
+
   static Future<String> signDataWithPrivateKey(
       String mnemonic, String coin, String path, String txData,
       [String passphrase = ""]) async {