diff --git a/pw_rpc/base_client_call.cc b/pw_rpc/base_client_call.cc
index 4c654e9..9ef3a31 100644
--- a/pw_rpc/base_client_call.cc
+++ b/pw_rpc/base_client_call.cc
@@ -35,11 +35,7 @@
     // If the call being assigned is active, replace it in the client's list
     // with a reference to the current object.
     other.Unregister();
-
-    // RegisterCall() only fails if there is already a call for the same
-    // (channel, service, method). As the existing call is unregistered, this
-    // error cannot happen.
-    other.client_->RegisterCall(*this).IgnoreError();
+    other.client_->RegisterCall(*this);
   }
 
   return *this;
@@ -92,12 +88,7 @@
   return Packet(type, channel_id_, service_id_, method_id_, payload);
 }
 
-void BaseClientCall::Register() {
-  // TODO(frolv): This is broken. If you try to replace an exisitng call with a
-  // new call to the same method on the same channel, the new call will fail to
-  // register. Instead, the new call should replace the existing one.
-  client_->RegisterCall(*this).IgnoreError();
-}
+void BaseClientCall::Register() { client_->RegisterCall(*this); }
 
 void BaseClientCall::Unregister() {
   if (active()) {
diff --git a/pw_rpc/base_client_call_test.cc b/pw_rpc/base_client_call_test.cc
index 7583966..0f78d37 100644
--- a/pw_rpc/base_client_call_test.cc
+++ b/pw_rpc/base_client_call_test.cc
@@ -36,6 +36,28 @@
   EXPECT_EQ(context.client().active_calls(), 0u);
 }
 
+TEST(BaseClientCall, Register_ReplacesExistingCall) {
+  ClientContextForTest context;
+  EXPECT_EQ(context.client().active_calls(), 0u);
+
+  BaseClientCall first(&context.client(),
+                       context.channel().id(),
+                       context.service_id(),
+                       context.method_id(),
+                       [](BaseClientCall&, const Packet&) {});
+  EXPECT_TRUE(first.active());
+  EXPECT_EQ(context.client().active_calls(), 1u);
+
+  BaseClientCall second(&context.client(),
+                        context.channel().id(),
+                        context.service_id(),
+                        context.method_id(),
+                        [](BaseClientCall&, const Packet&) {});
+  EXPECT_TRUE(second.active());
+  EXPECT_EQ(context.client().active_calls(), 1u);
+  EXPECT_FALSE(first.active());
+}
+
 TEST(BaseClientCall, Move_UnregistersOriginal) {
   ClientContextForTest context;
   EXPECT_EQ(context.client().active_calls(), 0u);
diff --git a/pw_rpc/client.cc b/pw_rpc/client.cc
index 3679e33..5b8b78f 100644
--- a/pw_rpc/client.cc
+++ b/pw_rpc/client.cc
@@ -98,20 +98,24 @@
   return channel;
 }
 
-Status Client::RegisterCall(BaseClientCall& call) {
+void Client::RegisterCall(BaseClientCall& call) {
   auto existing_call = std::find_if(calls_.begin(), calls_.end(), [&](auto& c) {
     return c.channel_id() == call.channel_id() &&
            c.service_id() == call.service_id() &&
            c.method_id() == call.method_id();
   });
+
   if (existing_call != calls_.end()) {
-    PW_LOG_WARN(
-        "RPC client tried to call same method multiple times; aborting.");
-    return Status::FailedPrecondition();
+    PW_LOG_DEBUG(
+        "RPC client called same method multiple times; canceling existing "
+        "call.");
+
+    // TODO(frolv): Invoke the existing_call's error callback once client calls
+    // are refactored as generic Calls.
+    existing_call->Unregister();
   }
 
   calls_.push_front(call);
-  return OkStatus();
 }
 
 }  // namespace pw::rpc
diff --git a/pw_rpc/public/pw_rpc/client.h b/pw_rpc/public/pw_rpc/client.h
index cac5825..be3a2f2 100644
--- a/pw_rpc/public/pw_rpc/client.h
+++ b/pw_rpc/public/pw_rpc/client.h
@@ -54,7 +54,7 @@
  private:
   friend class internal::BaseClientCall;
 
-  Status RegisterCall(internal::BaseClientCall& call);
+  void RegisterCall(internal::BaseClientCall& call);
   void RemoveCall(const internal::BaseClientCall& call) { calls_.remove(call); }
 
   std::span<internal::Channel> channels_;