diff --git a/.travis.yml b/.travis.yml
index 6df6b36..9db7c78 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,5 +5,7 @@ python:
   - "3.4"
   - "3.5"
   - "3.6"
+  - "3.7"
+  - "3.8"
 install: pip install tox-travis
 script: tox
diff --git a/README.rst b/README.rst
index 1416fdd..8409149 100644
--- a/README.rst
+++ b/README.rst
@@ -14,7 +14,7 @@
 .. |versions| image:: https://img.shields.io/pypi/pyversions/django_coverage_plugin.svg
     :target: https://pypi.python.org/pypi/django_coverage_plugin
     :alt: Supported Python Versions
-.. |djversions| image:: https://img.shields.io/badge/Django-1.8%20%7C%201.11%20%7C%202.0%20%7C%202.1-44b78b.svg
+.. |djversions| image:: https://img.shields.io/badge/Django-1.8%20%7C%201.11%20%7C%202.0%20%7C%202.1%20%7C%202.2%20%7C%203.0-44b78b.svg
     :target: https://pypi.python.org/pypi/django_coverage_plugin
     :alt: Supported Django Versions
 
@@ -26,9 +26,9 @@ Django Template Coverage.py Plugin
 
 A `coverage.py`_ plugin to measure test coverage of Django templates.
 
-Supported Python versions: 2.7, 3.4, 3.5 and 3.6.
+Supported Python versions: 2.7, 3.4, 3.5, 3.6, 3.7 and 3.8.
 
-Supported Django versions: 1.8, 1.11, 2.0, and 2.1.
+Supported Django versions: 1.8, 1.11, 2.0, 2.1, 2.2 and 3.0.
 
 Supported coverage.py versions are 4.0 and higher.
 
diff --git a/django_coverage_plugin/plugin.py b/django_coverage_plugin/plugin.py
index 60c61df..e777f4f 100644
--- a/django_coverage_plugin/plugin.py
+++ b/django_coverage_plugin/plugin.py
@@ -134,7 +134,13 @@ def read_template_source(filename):
         settings.configure()
 
     with open(filename, "rb") as f:
-        text = f.read().decode(settings.FILE_CHARSET)
+        # The FILE_CHARSET setting will be removed in 3.1:
+        # https://docs.djangoproject.com/en/3.0/ref/settings/#file-charset
+        if django.VERSION >= (3, 1):
+            charset = 'utf-8'
+        else:
+            charset = settings.FILE_CHARSET
+        text = f.read().decode(charset)
 
     return text
 
diff --git a/setup.py b/setup.py
index 4c1c435..174fdac 100644
--- a/setup.py
+++ b/setup.py
@@ -36,6 +36,8 @@ def read(*names, **kwargs):
 Programming Language :: Python :: 3.4
 Programming Language :: Python :: 3.5
 Programming Language :: Python :: 3.6
+Programming Language :: Python :: 3.7
+Programming Language :: Python :: 3.8
 Programming Language :: Python :: Implementation :: CPython
 Programming Language :: Python :: Implementation :: PyPy
 Topic :: Software Development :: Quality Assurance
@@ -46,6 +48,8 @@ def read(*names, **kwargs):
 Framework :: Django :: 1.11
 Framework :: Django :: 2.0
 Framework :: Django :: 2.1
+Framework :: Django :: 2.2
+Framework :: Django :: 3.0
 """
 
 setup(
@@ -63,7 +67,7 @@ def read(*names, **kwargs):
     url='https://github.com/nedbat/django_coverage_plugin',
     packages=['django_coverage_plugin'],
     install_requires=[
-        'coverage >= 4.0',
+        'coverage >= 4.0 , < 5',
         'six >= 1.4.0',
     ],
     license='Apache 2.0',
diff --git a/tox.ini b/tox.ini
index 58250ca..31061a9 100644
--- a/tox.ini
+++ b/tox.ini
@@ -16,9 +16,10 @@
 envlist =
     py27-django{18,19,110,111,111tip},
     py34-django{18,19,110,111,111tip,20},
-    py35-django{18,19,110,111,111tip,20,21,tip},
-    py36-django{18,19,110,111,111tip,20,21,tip},
-    py37-django{20,21,tip},
+    py35-django{18,19,110,111,111tip,20,21,22},
+    py36-django{18,19,110,111,111tip,20,21,22,30,tip},
+    py37-django{20,21,22,30,tip},
+    py38-django{22,30,tip},
     check,pkgcheck,doc
 
 [testenv]
@@ -31,6 +32,8 @@ deps =
     django111tip: https://github.com/django/django/archive/stable/1.11.x.tar.gz
     django20: Django>=2.0,<2.1
     django21: Django>=2.1,<2.2
+    django22: Django>=2.2,<3.0
+    django30: Django>=3.0,<3.1
     djangotip: https://github.com/django/django/archive/master.tar.gz
 
 commands =