diff --git a/esphome/components/api/api_frame_helper.cpp b/esphome/components/api/api_frame_helper.cpp
index d088a75c8a..5c5f1e8785 100644
--- a/esphome/components/api/api_frame_helper.cpp
+++ b/esphome/components/api/api_frame_helper.cpp
@@ -142,6 +142,7 @@ APIError APIFrameHelper::write_raw_iov_(const struct iovec *iov, int iovcnt, uin
             (iovcnt == 1) ? this->socket_->write(iov[0].iov_base, iov[0].iov_len) : this->socket_->writev(iov, iovcnt);
         if (sent == static_cast<ssize_t>(total_write_len))
           return APIError::OK;
+        // Partial write or -1: fall through to error check / enqueue below
       }
     }
     if (sent == -1) {
diff --git a/esphome/components/api/api_frame_helper_noise.cpp b/esphome/components/api/api_frame_helper_noise.cpp
index 0c0c069b53..156fcec314 100644
--- a/esphome/components/api/api_frame_helper_noise.cpp
+++ b/esphome/components/api/api_frame_helper_noise.cpp
@@ -504,7 +504,8 @@ APIError APINoiseFrameHelper::write_protobuf_packet(uint8_t type, ProtoWriteBuff
   APIError aerr = this->encrypt_noise_message_(buf_start, msg, iov);
   if (aerr != APIError::OK)
     return aerr;
-  return this->write_raw_fast_buf_(iov.iov_base, static_cast<uint16_t>(iov.iov_len));
+  // buf_start and iov.iov_base point to the same location
+  return this->write_raw_fast_buf_(buf_start, static_cast<uint16_t>(iov.iov_len));
 }
 
 APIError APINoiseFrameHelper::write_protobuf_messages(ProtoWriteBuffer buffer, std::span<const MessageInfo> messages) {