diff --git a/pvlib/atmosphere.py b/pvlib/atmosphere.py
index ab4446a9c3..743010e398 100644
--- a/pvlib/atmosphere.py
+++ b/pvlib/atmosphere.py
@@ -3,8 +3,6 @@
 absolute airmass and to determine pressure from altitude or vice versa.
 """
 
-from __future__ import division
-
 from warnings import warn
 
 import numpy as np
@@ -211,8 +209,7 @@ def get_relative_airmass(zenith, model='kastenyoung1989'):
     Sandia Report, (2012).
     '''
 
-    # need to filter first because python 2.7 does not support raising a
-    # negative number to a negative power.
+    # set zenith values greater than 90 to nans
     z = np.where(zenith > 90, np.nan, zenith)
     zenith_rad = np.radians(z)
 
diff --git a/pvlib/clearsky.py b/pvlib/clearsky.py
index 6543244e30..0aa80129d9 100644
--- a/pvlib/clearsky.py
+++ b/pvlib/clearsky.py
@@ -3,8 +3,6 @@
 to calculate clear sky GHI, DNI, and DHI.
 """
 
-from __future__ import division
-
 import os
 from collections import OrderedDict
 import calendar
diff --git a/pvlib/iotools/ecmwf_macc.py b/pvlib/iotools/ecmwf_macc.py
index ef0ee2259c..4fa8ebd061 100644
--- a/pvlib/iotools/ecmwf_macc.py
+++ b/pvlib/iotools/ecmwf_macc.py
@@ -2,7 +2,6 @@
 Read data from ECMWF MACC Reanalysis.
 """
 
-from __future__ import division
 import threading
 import pandas as pd
 
diff --git a/pvlib/iotools/epw.py b/pvlib/iotools/epw.py
index 6b6c5ddd2d..4a714d0f2d 100644
--- a/pvlib/iotools/epw.py
+++ b/pvlib/iotools/epw.py
@@ -3,13 +3,7 @@
 """
 
 import io
-
-try:
-    # python 2 compatibility
-    from urllib2 import urlopen, Request
-except ImportError:
-    from urllib.request import urlopen, Request
-
+from urllib.request import urlopen, Request
 import pandas as pd
 
 
diff --git a/pvlib/iotools/psm3.py b/pvlib/iotools/psm3.py
index 560a259962..caa7ee9813 100644
--- a/pvlib/iotools/psm3.py
+++ b/pvlib/iotools/psm3.py
@@ -7,11 +7,7 @@
 import io
 import requests
 import pandas as pd
-# Python-2 compatible JSONDecodeError
-try:
-    from json import JSONDecodeError
-except ImportError:
-    JSONDecodeError = ValueError
+from json import JSONDecodeError
 
 URL = "http://developer.nrel.gov/api/solar/nsrdb_psm3_download.csv"
 
diff --git a/pvlib/iotools/surfrad.py b/pvlib/iotools/surfrad.py
index 503b9da732..22e451cfeb 100644
--- a/pvlib/iotools/surfrad.py
+++ b/pvlib/iotools/surfrad.py
@@ -2,13 +2,7 @@
 Import functions for NOAA SURFRAD Data.
 """
 import io
-
-try:
-    # python 2 compatibility
-    from urllib2 import urlopen, Request
-except ImportError:
-    from urllib.request import urlopen, Request
-
+from urllib.request import urlopen, Request
 import pandas as pd
 import numpy as np
 
diff --git a/pvlib/iotools/tmy.py b/pvlib/iotools/tmy.py
index 9c5ba9e9ca..a3860c352d 100644
--- a/pvlib/iotools/tmy.py
+++ b/pvlib/iotools/tmy.py
@@ -5,13 +5,7 @@
 import datetime
 import io
 import re
-
-try:
-    # python 2 compatibility
-    from urllib2 import urlopen, Request
-except ImportError:
-    from urllib.request import urlopen, Request
-
+from urllib.request import urlopen, Request
 import dateutil
 import pandas as pd
 
@@ -160,7 +154,7 @@ def read_tmy3(filename=None, coerce_year=None, recolumn=True):
         try:
             filename = _interactive_load()
         except ImportError:
-            raise ImportError('Interactive load failed. Tkinter not supported '
+            raise ImportError('Interactive load failed. tkinter not supported '
                               'on this system. Try installing X-Quartz and '
                               'reloading')
 
@@ -210,9 +204,9 @@ def read_tmy3(filename=None, coerce_year=None, recolumn=True):
 
 
 def _interactive_load():
-    import Tkinter
-    from tkFileDialog import askopenfilename
-    Tkinter.Tk().withdraw()  # Start interactive file input
+    import tkinter
+    from tkinter.filedialog import askopenfilename
+    tkinter.Tk().withdraw()  # Start interactive file input
     return askopenfilename()
 
 
@@ -406,7 +400,7 @@ def read_tmy2(filename):
         try:
             filename = _interactive_load()
         except ImportError:
-            raise ImportError('Interactive load failed. Tkinter not supported '
+            raise ImportError('Interactive load failed. tkinter not supported '
                               'on this system. Try installing X-Quartz and '
                               'reloading')
 
diff --git a/pvlib/irradiance.py b/pvlib/irradiance.py
index 000cf3216c..494d13be5a 100644
--- a/pvlib/irradiance.py
+++ b/pvlib/irradiance.py
@@ -4,8 +4,6 @@
 irradiance, and total irradiance under various conditions.
 """
 
-from __future__ import division
-
 import datetime
 from collections import OrderedDict
 from functools import partial
diff --git a/pvlib/pvsystem.py b/pvlib/pvsystem.py
index 35701bd3a2..c3aab0147e 100644
--- a/pvlib/pvsystem.py
+++ b/pvlib/pvsystem.py
@@ -3,16 +3,10 @@
 performance of PV modules and inverters.
 """
 
-from __future__ import division
-
 from collections import OrderedDict
 import io
 import os
-try:
-    from urllib2 import urlopen
-except ImportError:
-    from urllib.request import urlopen
-
+from urllib.request import urlopen
 import numpy as np
 import pandas as pd
 
@@ -1632,14 +1626,8 @@ def retrieve_sam(name=None, path=None):
         else:
             csvdata = path
     elif name is None and path is None:
-        try:
-            # python 2
-            import Tkinter as tkinter
-            from tkFileDialog import askopenfilename
-        except ImportError:
-            # python 3
-            import tkinter
-            from tkinter.filedialog import askopenfilename
+        import tkinter
+        from tkinter.filedialog import askopenfilename
 
         tkinter.Tk().withdraw()
         csvdata = askopenfilename()
diff --git a/pvlib/solarposition.py b/pvlib/solarposition.py
index d55737040b..be7f33aefa 100644
--- a/pvlib/solarposition.py
+++ b/pvlib/solarposition.py
@@ -8,7 +8,6 @@
 # Tony Lorenzo (@alorenzo175), University of Arizona, 2015
 # Cliff hansen (@cwhanse), Sandia National Laboratories, 2018
 
-from __future__ import division
 import os
 import datetime as dt
 try:
diff --git a/pvlib/spa.py b/pvlib/spa.py
index 3a44a2efed..6c99a03f0c 100644
--- a/pvlib/spa.py
+++ b/pvlib/spa.py
@@ -6,7 +6,6 @@
 # Contributors:
 # Created by Tony Lorenzo (@alorenzo175), Univ. of Arizona, 2015
 
-from __future__ import division
 import os
 import threading
 import warnings
diff --git a/pvlib/test/conftest.py b/pvlib/test/conftest.py
index e91adb8689..d26ff00f4b 100644
--- a/pvlib/test/conftest.py
+++ b/pvlib/test/conftest.py
@@ -41,8 +41,6 @@ def inner():
 data_dir = os.path.join(test_dir, os.pardir, 'data')
 
 
-has_python2 = parse_version(platform.python_version()) < parse_version('3')
-
 platform_is_windows = platform.system() == 'Windows'
 skip_windows = pytest.mark.skipif(platform_is_windows,
                                   reason='does not run on windows')
diff --git a/pvlib/test/test_conftest.py b/pvlib/test/test_conftest.py
index e2a836537c..14cc7e5d79 100644
--- a/pvlib/test/test_conftest.py
+++ b/pvlib/test/test_conftest.py
@@ -1,10 +1,9 @@
 import pytest
 
-from conftest import fail_on_pvlib_version, platform_is_windows, has_python2
+from conftest import fail_on_pvlib_version
 
 
-# allow xpass for python 2 on windows
-@pytest.mark.xfail(strict=(not (platform_is_windows and has_python2)),
+@pytest.mark.xfail(strict=True,
                    reason='fail_on_pvlib_version should cause test to fail')
 @fail_on_pvlib_version('0.0')
 def test_fail_on_pvlib_version():
@@ -16,8 +15,7 @@ def test_fail_on_pvlib_version_pass():
     pass
 
 
-@pytest.mark.xfail(strict=(not (platform_is_windows and has_python2)),
-                   reason='ensure that the test is called')
+@pytest.mark.xfail(strict=True, reason='ensure that the test is called')
 @fail_on_pvlib_version('100000.0')
 def test_fail_on_pvlib_version_fail_in_test():
     raise Exception
diff --git a/pvlib/test/test_ecmwf_macc.py b/pvlib/test/test_ecmwf_macc.py
index de0e389403..8823b789e5 100644
--- a/pvlib/test/test_ecmwf_macc.py
+++ b/pvlib/test/test_ecmwf_macc.py
@@ -2,7 +2,6 @@
 tests for :mod:`pvlib.iotools.ecmwf_macc`
 """
 
-from __future__ import division
 import os
 import datetime
 import numpy as np
diff --git a/pvlib/tracking.py b/pvlib/tracking.py
index f81b0e8571..9859022bc4 100644
--- a/pvlib/tracking.py
+++ b/pvlib/tracking.py
@@ -1,5 +1,3 @@
-from __future__ import division
-
 import numpy as np
 import pandas as pd