diff --git a/esphome/components/pca9685/pca9685_output.cpp b/esphome/components/pca9685/pca9685_output.cpp
index 77e3d5a6c6..89a6bcdcc0 100644
--- a/esphome/components/pca9685/pca9685_output.cpp
+++ b/esphome/components/pca9685/pca9685_output.cpp
@@ -8,11 +8,7 @@ namespace pca9685 {
 
 static const char *const TAG = "pca9685";
 
-const uint8_t PCA9685_MODE_INVERTED = 0x10;
-const uint8_t PCA9685_MODE_OUTPUT_ONACK = 0x08;
-const uint8_t PCA9685_MODE_OUTPUT_TOTEM_POLE = 0x04;
-const uint8_t PCA9685_MODE_OUTNE_HIGHZ = 0x02;
-const uint8_t PCA9685_MODE_OUTNE_LOW = 0x01;
+// PCA9685 mode constants are now inline constexpr in pca9685_output.h
 
 static const uint8_t PCA9685_REGISTER_SOFTWARE_RESET = 0x06;
 static const uint8_t PCA9685_REGISTER_MODE1 = 0x00;
diff --git a/esphome/components/pca9685/pca9685_output.h b/esphome/components/pca9685/pca9685_output.h
index 288c923d4c..785cc974da 100644
--- a/esphome/components/pca9685/pca9685_output.h
+++ b/esphome/components/pca9685/pca9685_output.h
@@ -13,15 +13,15 @@ enum class PhaseBalancer {
 };
 
 /// Inverts polarity of channel output signal
-extern const uint8_t PCA9685_MODE_INVERTED;
+inline constexpr uint8_t PCA9685_MODE_INVERTED = 0x10;
 /// Channel update happens upon ACK (post-set) rather than on STOP (endTransmission)
-extern const uint8_t PCA9685_MODE_OUTPUT_ONACK;
+inline constexpr uint8_t PCA9685_MODE_OUTPUT_ONACK = 0x08;
 /// Use a totem-pole (push-pull) style output rather than an open-drain structure.
-extern const uint8_t PCA9685_MODE_OUTPUT_TOTEM_POLE;
+inline constexpr uint8_t PCA9685_MODE_OUTPUT_TOTEM_POLE = 0x04;
 /// For active low output enable, sets channel output to high-impedance state
-extern const uint8_t PCA9685_MODE_OUTNE_HIGHZ;
+inline constexpr uint8_t PCA9685_MODE_OUTNE_HIGHZ = 0x02;
 /// Similarly, sets channel output to high if in totem-pole mode, otherwise
-extern const uint8_t PCA9685_MODE_OUTNE_LOW;
+inline constexpr uint8_t PCA9685_MODE_OUTNE_LOW = 0x01;
 
 class PCA9685Output;