diff --git a/client/src/main/kotlin/io/provenance/client/grpc/AbstractPbClient.kt b/client/src/main/kotlin/io/provenance/client/grpc/AbstractPbClient.kt
index fcf7c59..01bbc46 100644
--- a/client/src/main/kotlin/io/provenance/client/grpc/AbstractPbClient.kt
+++ b/client/src/main/kotlin/io/provenance/client/grpc/AbstractPbClient.kt
@@ -121,11 +121,15 @@ open class AbstractPbClient<T : ManagedChannelBuilder<T>>(
         gasEstimate: GasEstimate,
         mode: ServiceOuterClass.BroadcastMode = ServiceOuterClass.BroadcastMode.BROADCAST_MODE_SYNC,
         txHashHandler: PreBroadcastTxHashHandler? = null,
-        signatures: List<ByteArray?> = emptyList(),
+        signatures: List<ByteArray?> = List(baseReq.signers.size) { null },
     ): ServiceOuterClass.BroadcastTxResponse {
         val authInfoBytes = baseReq.buildAuthInfo(gasEstimate).toByteString()
         val txBodyBytes = baseReq.body.toByteString()
 
+        require(signatures.size == baseReq.signers.size) {
+            "The number of signatures must match the number of signers. A null/empty signature entry will sign using the Signer implementation."
+        }
+
         val txRaw = baseReq.signers.mapIndexed { index, baseReqSigner ->
             signatures[index]?.takeIf { it.isNotEmpty() }
                 ?: baseReqSigner.signer.sign(
@@ -169,7 +173,7 @@ open class AbstractPbClient<T : ManagedChannelBuilder<T>>(
         feeGranter: String? = null,
         feePayer: String? = null,
         txHashHandler: PreBroadcastTxHashHandler? = null,
-        signatures: List<ByteArray?> = emptyList(),
+        signatures: List<ByteArray?> = List(signers.size) { null },
     ): ServiceOuterClass.BroadcastTxResponse =
         baseRequest(
             txBody = txBody,