diff --git a/src/modules/ekf2/EKF/common.h b/src/modules/ekf2/EKF/common.h
index 880df1d4fe..aaabe89eaa 100644
--- a/src/modules/ekf2/EKF/common.h
+++ b/src/modules/ekf2/EKF/common.h
@@ -95,8 +95,7 @@ enum class VelocityFrame : uint8_t {
 enum GeoDeclinationMask : uint8_t {
 	// Bit locations for mag_declination_source
 	USE_GEO_DECL  = (1<<0), ///< set to true to use the declination from the geo library when the GPS position becomes available, set to false to always use the EKF2_MAG_DECL value
-	SAVE_GEO_DECL = (1<<1), ///< set to true to set the EKF2_MAG_DECL parameter to the value returned by the geo library
-	FUSE_DECL     = (1<<2)  ///< set to true if the declination is always fused as an observation to constrain drift when 3-axis fusion is performed
+	SAVE_GEO_DECL = (1<<1)  ///< set to true to set the EKF2_MAG_DECL parameter to the value returned by the geo library
 };
 
 enum MagFuseType : uint8_t {
@@ -361,7 +360,7 @@ struct parameters {
 	float mag_noise{5.0e-2f};               ///< measurement noise used for 3-axis magnetometer fusion (Gauss)
 	float mag_declination_deg{0.0f};        ///< magnetic declination (degrees)
 	float mag_innov_gate{3.0f};             ///< magnetometer fusion innovation consistency gate size (STD)
-	int32_t mag_declination_source{7};      ///< bitmask used to control the handling of declination data
+	int32_t mag_declination_source{3};      ///< bitmask used to control the handling of declination data
 	int32_t mag_fusion_type{0};             ///< integer used to specify the type of magnetometer fusion used
 	float mag_acc_gate{0.5f};               ///< when in auto select mode, heading fusion will be used when manoeuvre accel is lower than this (m/sec**2)
 
diff --git a/src/modules/ekf2/EKF/mag_3d_control.cpp b/src/modules/ekf2/EKF/mag_3d_control.cpp
index 79ed2b6c9d..41192f2cbf 100644
--- a/src/modules/ekf2/EKF/mag_3d_control.cpp
+++ b/src/modules/ekf2/EKF/mag_3d_control.cpp
@@ -91,9 +91,8 @@ void Ekf::controlMag3DFusion(const magSample &mag_sample, const bool common_star
 	// if we are using 3-axis magnetometer fusion, but without external NE aiding,
 	// then the declination must be fused as an observation to prevent long term heading drift
 	// fusing declination when gps aiding is available is optional.
-	const bool mag_decl_user_selected = (_params.mag_declination_source & GeoDeclinationMask::FUSE_DECL);
 	const bool not_using_ne_aiding = !_control_status.flags.gps && !_control_status.flags.aux_gpos;
-	_control_status.flags.mag_dec = (_control_status.flags.mag && ((not_using_ne_aiding || !_control_status.flags.mag_aligned_in_flight) || mag_decl_user_selected));
+	_control_status.flags.mag_dec = (_control_status.flags.mag && (not_using_ne_aiding || !_control_status.flags.mag_aligned_in_flight));
 
 	if (_control_status.flags.mag) {
 		aid_src.timestamp_sample = mag_sample.time_us;
diff --git a/src/modules/ekf2/ekf2_params.c b/src/modules/ekf2/ekf2_params.c
index ebeae0e8e1..b43f30440d 100644
--- a/src/modules/ekf2/ekf2_params.c
+++ b/src/modules/ekf2/ekf2_params.c
@@ -474,14 +474,12 @@ PARAM_DEFINE_FLOAT(EKF2_MAG_GATE, 3.0f);
  * Set bits in the following positions to enable functions.
  * 0 : Set to true to use the declination from the geo_lookup library when the GPS position becomes available, set to false to always use the EKF2_MAG_DECL value.
  * 1 : Set to true to save the EKF2_MAG_DECL parameter to the value returned by the EKF when the vehicle disarms.
- * 2 : Set to true to always use the declination as an observation when 3-axis magnetometer fusion is being used.
  *
  * @group EKF2
  * @min 0
- * @max 7
+ * @max 3
  * @bit 0 use geo_lookup declination
  * @bit 1 save EKF2_MAG_DECL on disarm
- * @bit 2 use declination as an observation
  * @reboot_required true
  */
 PARAM_DEFINE_INT32(EKF2_DECL_TYPE, 3);