diff --git a/bilby/gw/source.py b/bilby/gw/source.py
index cfc50597c8ea56fdda7c41acc6118af0774b16f0..6f1253f131602ebe4b2a1718377fa993aeafca6c 100644
--- a/bilby/gw/source.py
+++ b/bilby/gw/source.py
@@ -195,9 +195,8 @@ def _base_lal_cbc_fd_waveform(
         Secondary tilt angle
     phi_jl: float
         Azimuthal angle between the total and orbital angular momenta
-    iota: float
+    theta_jn: float
         Orbital inclination
-        FIXME: this should be theta_jn
     phase: float
         The phase at coalescence
     eccentricity: float
@@ -236,6 +235,7 @@ def _base_lal_cbc_fd_waveform(
         spin_2x = 0.0
         spin_2y = 0.0
         spin_2z = a_2 * np.cos(tilt_2)
+        iota = theta_jn
     else:
         iota, spin_1x, spin_1y, spin_1z, spin_2x, spin_2y, spin_2z = (
             transform_precessing_spins(
diff --git a/test/gw_source_test.py b/test/gw_source_test.py
index 9ee8b2895426b479b69eeb10c2efcc3918122e79..976a4627b572b91efdd18da72501cb944453f861 100644
--- a/test/gw_source_test.py
+++ b/test/gw_source_test.py
@@ -11,7 +11,7 @@ class TestLalBBH(unittest.TestCase):
     def setUp(self):
         self.parameters = dict(
             mass_1=30.0, mass_2=30.0, luminosity_distance=400.0, a_1=0.0,
-            tilt_1=0.0, phi_12=0.0, a_2=0.0, tilt_2=0.0, phi_jl=0.0, iota=0.0,
+            tilt_1=0.0, phi_12=0.0, a_2=0.0, tilt_2=0.0, phi_jl=0.0, theta_jn=0.0,
             phase=0.0)
         self.waveform_kwargs = dict(
             waveform_approximant='IMRPhenomPv2', reference_frequency=50.0,
@@ -54,7 +54,7 @@ class TestLalBNS(unittest.TestCase):
     def setUp(self):
         self.parameters = dict(
             mass_1=1.4, mass_2=1.4, luminosity_distance=400.0, chi_1=0.0,
-            chi_2=0.0, iota=0.0, phase=0.0, lambda_1=0.0, lambda_2=0.0)
+            chi_2=0.0, theta_jn=0.0, phase=0.0, lambda_1=0.0, lambda_2=0.0)
         self.waveform_kwargs = dict(
             waveform_approximant='TaylorF2', reference_frequency=50.0,
             minimum_frequency=20.0)
@@ -104,7 +104,7 @@ class TestEccentricLalBBH(unittest.TestCase):
 
     def setUp(self):
         self.parameters = dict(
-            mass_1=30.0, mass_2=30.0, luminosity_distance=400.0, iota=0.0,
+            mass_1=30.0, mass_2=30.0, luminosity_distance=400.0, theta_jn=0.0,
             phase=0.0, eccentricity=0.1)
         self.waveform_kwargs = dict(
             waveform_approximant='EccentricFD', reference_frequency=10.0,
@@ -154,7 +154,7 @@ class TestROQBBH(unittest.TestCase):
 
         self.parameters = dict(
             mass_1=30.0, mass_2=30.0, luminosity_distance=400.0, a_1=0.0,
-            tilt_1=0.0, phi_12=0.0, a_2=0.0, tilt_2=0.0, phi_jl=0.0, iota=0.0,
+            tilt_1=0.0, phi_12=0.0, a_2=0.0, tilt_2=0.0, phi_jl=0.0, theta_jn=0.0,
             phase=0.0)
         self.waveform_kwargs = dict(
             frequency_nodes_linear=fnodes_linear,