diff --git a/src/qinfer/tomography/bases.py b/src/qinfer/tomography/bases.py
index b035376..4a120b3 100644
--- a/src/qinfer/tomography/bases.py
+++ b/src/qinfer/tomography/bases.py
@@ -49,7 +49,7 @@
     import qutip as qt
     from distutils.version import LooseVersion
     _qt_version = LooseVersion(qt.version.version)
-    if _qt_version < LooseVersion('3.1'):
+    if _qt_version < LooseVersion('3.2'):
         qt = None
 except ImportError:
     qt = None
diff --git a/src/qinfer/tomography/distributions.py b/src/qinfer/tomography/distributions.py
index 36eff24..ec7906d 100644
--- a/src/qinfer/tomography/distributions.py
+++ b/src/qinfer/tomography/distributions.py
@@ -50,7 +50,7 @@
     import qutip as qt
     from distutils.version import LooseVersion
     _qt_version = LooseVersion(qt.version.version)
-    if _qt_version < LooseVersion('3.1'):
+    if _qt_version < LooseVersion('3.2'):
         qt = None
 except ImportError:
     qt = None
diff --git a/src/qinfer/tomography/expdesign.py b/src/qinfer/tomography/expdesign.py
index 22911b0..4025cfa 100644
--- a/src/qinfer/tomography/expdesign.py
+++ b/src/qinfer/tomography/expdesign.py
@@ -56,7 +56,7 @@
     import qutip as qt
     from distutils.version import LooseVersion
     _qt_version = LooseVersion(qt.version.version)
-    if _qt_version < LooseVersion('3.1'):
+    if _qt_version < LooseVersion('3.2'):
         qt = None
 except ImportError:
     qt = None
diff --git a/src/qinfer/tomography/legacy.py b/src/qinfer/tomography/legacy.py
index 2a61e83..700bf61 100644
--- a/src/qinfer/tomography/legacy.py
+++ b/src/qinfer/tomography/legacy.py
@@ -48,7 +48,7 @@
     import qutip as qt
     from distutils.version import LooseVersion
     _qt_version = LooseVersion(qt.version.version)
-    if _qt_version < LooseVersion('3.1'):
+    if _qt_version < LooseVersion('3.2'):
         qt = None
 except ImportError:
     qt = None
diff --git a/src/qinfer/tomography/plotting_tools.py b/src/qinfer/tomography/plotting_tools.py
index 3580976..e962c6d 100644
--- a/src/qinfer/tomography/plotting_tools.py
+++ b/src/qinfer/tomography/plotting_tools.py
@@ -54,7 +54,7 @@
     import qutip as qt
     from distutils.version import LooseVersion
     _qt_version = LooseVersion(qt.version.version)
-    if _qt_version < LooseVersion('3.1'):
+    if _qt_version < LooseVersion('3.2'):
         qt = None
 except ImportError:
     qt = None