diff --git a/image_analysis/scale_merge/Merge.cpp b/image_analysis/scale_merge/Merge.cpp
index 4d33f60a..92f1f061 100644
--- a/image_analysis/scale_merge/Merge.cpp
+++ b/image_analysis/scale_merge/Merge.cpp
@@ -478,7 +478,8 @@ void CalcPossibleReflections(int space_group_number ,
                              double d_min,
                              double d_max,
                              const ResolutionShells &shells,
-                             std::vector<ShellAccum> &acc) {
+                             std::vector<ShellAccum> &acc,
+                             bool merge_friedel) {
     gemmi::UnitCell gemmi_cell = cell;
     const gemmi::SpaceGroup *sg = gemmi::find_spacegroup_by_number(space_group_number);
     if (sg == nullptr)
@@ -487,6 +488,7 @@ void CalcPossibleReflections(int space_group_number ,
 
     // Generate unique reflections
     std::vector<gemmi::Miller> possible_hkls = gemmi::make_miller_vector(gemmi_cell, sg, d_min, d_max, true);
+    const gemmi::GroupOps gops = sg->operations();
     CrystalLattice lattice(cell);
     const auto astar = lattice.Astar();
     const auto bstar = lattice.Bstar();
@@ -503,7 +505,10 @@ void CalcPossibleReflections(int space_group_number ,
             continue;
         const int s = *shell;
         if (s >= 0 && s < acc.size())
-            acc[s].possible++;
+            // Anomalous (no Friedel merge): an acentric reflection has two unique members (I+ and I-),
+            // a centric one only one — match how unique_reflections is counted, so completeness stays
+            // <=100% instead of approaching 200%.
+            acc[s].possible += (merge_friedel || gops.is_reflection_centric(hkl)) ? 1 : 2;
     }
 }
 
@@ -556,7 +561,7 @@ MergeStatistics MergeOnTheFly::MergeStats(const std::vector<MergedReflection> &m
 
     if (reference_cell.has_value())
         CalcPossibleReflections(space_group_number, reference_cell.value(),
-            d_min_pad, d_max_pad, shells, acc);
+            d_min_pad, d_max_pad, shells, acc, scaling_settings.GetMergeFriedel());
 
     CorrelationCoefficient cc_half_overall;
     CorrelationCoefficient cc_ref_overall;