diff --git a/flavio/physics/wdecays/mw.py b/flavio/physics/wdecays/mw.py
index c33460cc..2bd188be 100644
--- a/flavio/physics/wdecays/mw.py
+++ b/flavio/physics/wdecays/mw.py
@@ -41,7 +41,7 @@ def dmW_SMEFT(par, C):
     ch2 = 1 - sh2
     ch = sqrt(ch2)
     Dh = ch * sh / ((ch**2 - sh**2) * 2 * sqrt(2) * par['GF'])
-    return Dh * (4 * C['phiWB'] + ch / sh * C['phiD'] + 2 * sh / ch * (C['phil3_11'] + C['phil3_22']) - 2 * sh / ch * C['ll_1221']).real
+    return Dh * (4 * C['phiWB'] + ch / sh * C['phiD'] + 2 * sh / ch * (C['phil3_11'] + C['phil3_22'] - C['ll_1221'] / 2)).real
 
 def mW(wc_obj, par):
     r"""$W$ pole mass."""
diff --git a/flavio/physics/zdecays/smeftew.py b/flavio/physics/zdecays/smeftew.py
index 1ad8da78..3e2b1712 100644
--- a/flavio/physics/zdecays/smeftew.py
+++ b/flavio/physics/zdecays/smeftew.py
@@ -21,7 +21,7 @@
 
 
 def d_GF(par, C):
-    return 1 / (sqrt(2) * par['GF']) * (sqrt(2) * (C['phil3_22'] + C['phil3_11']) / 2 - C['ll_1221'] / sqrt(2))
+    return 1 / (sqrt(2) * par['GF']) * sqrt(2) / 2 * (C['phil3_22'] + C['phil3_11'] - C['ll_1221'] / 2)
 
 
 def _sinthetahat2(par):
@@ -35,7 +35,7 @@ def d_sh2(par, C):
     ch = sqrt(ch2)
     s2h = 2 * ch * sh # sin(2 * thetahat)
     c2h = ch**2 - sh**2 # cos(2 * thetahat)
-    dC = s2h * (C['phiD'] + 2 * (C['phil3_22'] + C['phil3_11']) - 2 * C['ll_1221']) + 4 * C['phiWB']
+    dC = s2h * (C['phiD'] + 2 * (C['phil3_22'] + C['phil3_11'] - C['ll_1221'] / 2)) + 4 * C['phiWB']
     return s2h / (8 * c2h * sqrt(2) * par['GF']) * dC