diff --git a/esphome/core/component.cpp b/esphome/core/component.cpp
index 3542a9547c..8bd7afd8c7 100644
--- a/esphome/core/component.cpp
+++ b/esphome/core/component.cpp
@@ -26,16 +26,22 @@ static const char *const TAG = "component";
 // 1. Components are never destroyed in ESPHome
 // 2. Failed components remain failed (no recovery mechanism)
 // 3. Memory usage is minimal (only failures with custom messages are stored)
+
+// Using namespace-scope static to avoid guard variables (saves 16 bytes total)
+// This is safe because ESPHome is single-threaded during initialization
+namespace {
+// Error messages for failed components
+std::unique_ptr<std::vector<std::pair<const Component *, const char *>>> component_error_messages;
+// Setup priority overrides - freed after setup completes
+std::unique_ptr<std::vector<std::pair<const Component *, float>>> setup_priority_overrides;
+}  // namespace
+
 static std::unique_ptr<std::vector<std::pair<const Component *, const char *>>> &get_component_error_messages() {
-  static std::unique_ptr<std::vector<std::pair<const Component *, const char *>>> instance;
-  return instance;
+  return component_error_messages;
 }
 
-// Setup priority overrides - freed after setup completes
-// Typically < 5 entries, lazy allocated
 static std::unique_ptr<std::vector<std::pair<const Component *, float>>> &get_setup_priority_overrides() {
-  static std::unique_ptr<std::vector<std::pair<const Component *, float>>> instance;
-  return instance;
+  return setup_priority_overrides;
 }
 
 namespace setup_priority {
diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index 7d9b86fccd..6074d95757 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -460,9 +460,15 @@ int8_t step_to_accuracy_decimals(float step) {
   return str.length() - dot_pos - 1;
 }
 
-static const std::string BASE64_CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-                                        "abcdefghijklmnopqrstuvwxyz"
-                                        "0123456789+/";
+// Use C-style string constant to store in ROM instead of RAM (saves 24 bytes)
+static constexpr const char *BASE64_CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+                                            "abcdefghijklmnopqrstuvwxyz"
+                                            "0123456789+/";
+
+static inline uint8_t base64_find_char(char c) {
+  const char *pos = strchr(BASE64_CHARS, c);
+  return pos ? (pos - BASE64_CHARS) : 0;
+}
 
 static inline bool is_base64(char c) { return (isalnum(c) || (c == '+') || (c == '/')); }
 
@@ -531,7 +537,7 @@ std::vector<uint8_t> base64_decode(const std::string &encoded_string) {
     in++;
     if (i == 4) {
       for (i = 0; i < 4; i++)
-        char_array_4[i] = BASE64_CHARS.find(char_array_4[i]);
+        char_array_4[i] = base64_find_char(char_array_4[i]);
 
       char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
       char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
@@ -548,7 +554,7 @@ std::vector<uint8_t> base64_decode(const std::string &encoded_string) {
       char_array_4[j] = 0;
 
     for (j = 0; j < 4; j++)
-      char_array_4[j] = BASE64_CHARS.find(char_array_4[j]);
+      char_array_4[j] = base64_find_char(char_array_4[j]);
 
     char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
     char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);