diff --git a/src/ipaclustercheck/ipa/plugin.py b/src/ipaclustercheck/ipa/plugin.py
index a1119886..6ca0e1e4 100644
--- a/src/ipaclustercheck/ipa/plugin.py
+++ b/src/ipaclustercheck/ipa/plugin.py
@@ -92,7 +92,7 @@ def load_files(self, dir):
             fname = join(dir, file)
             logger.debug("Reading %s", fname)
             try:
-                with open(fname, 'r') as fd:
+                with open(fname, 'r', encoding="utf-8") as fd:
                     data = fd.read()
             except Exception as e:
                 logger.error("Unable to read %s: %s", fname, e)
diff --git a/src/ipahealthcheck/core/core.py b/src/ipahealthcheck/core/core.py
index 685dbd72..610b8736 100644
--- a/src/ipahealthcheck/core/core.py
+++ b/src/ipahealthcheck/core/core.py
@@ -409,7 +409,7 @@ def run_healthcheck(self):
 
         if 'infile' in options and options.infile:
             try:
-                with open(options.infile, 'r') as f:
+                with open(options.infile, 'r', encoding="utf-8") as f:
                     raw_data = f.read()
 
                 json_data = json.loads(raw_data)
diff --git a/src/ipahealthcheck/core/output.py b/src/ipahealthcheck/core/output.py
index b29bc0c8..225e40af 100644
--- a/src/ipahealthcheck/core/output.py
+++ b/src/ipahealthcheck/core/output.py
@@ -61,7 +61,7 @@ def render(self, results):
     def write_file(self, output):
         """Write the output to a file or sys.stdout"""
         if self.filename:
-            with open(self.filename, 'w') as fd:
+            with open(self.filename, 'w', encoding="utf-8") as fd:
                 fd.write(output)
         else:
             sys.stdout.write(output)
diff --git a/src/ipahealthcheck/ipa/certs.py b/src/ipahealthcheck/ipa/certs.py
index 71971184..cf023077 100644
--- a/src/ipahealthcheck/ipa/certs.py
+++ b/src/ipahealthcheck/ipa/certs.py
@@ -173,7 +173,7 @@ def get_dogtag_cert_password():
     """
     ca_passwd = None
     token = 'internal'
-    with open(paths.PKI_TOMCAT_PASSWORD_CONF, 'r') as f:
+    with open(paths.PKI_TOMCAT_PASSWORD_CONF, 'r', encoding="utf-8") as f:
         for line in f:
             (tok, pin) = line.split('=', 1)
             if token == tok:
diff --git a/src/ipahealthcheck/ipa/proxy.py b/src/ipahealthcheck/ipa/proxy.py
index 5b4fcee0..a22ac14a 100644
--- a/src/ipahealthcheck/ipa/proxy.py
+++ b/src/ipahealthcheck/ipa/proxy.py
@@ -22,7 +22,7 @@ def read_ipa_pki_proxy():
 
        Split out to make it easier to mock
     """
-    with open(paths.HTTPD_IPA_PKI_PROXY_CONF, "r") as fd:
+    with open(paths.HTTPD_IPA_PKI_PROXY_CONF, "r", encoding="utf-8") as fd:
         lines = fd.readlines()
 
     return lines
diff --git a/src/ipahealthcheck/system/filesystemspace.py b/src/ipahealthcheck/system/filesystemspace.py
index 379ae66c..b77515ca 100644
--- a/src/ipahealthcheck/system/filesystemspace.py
+++ b/src/ipahealthcheck/system/filesystemspace.py
@@ -13,10 +13,10 @@
 
 def in_container():
     """Determine if we're running in a container."""
-    with open('/proc/1/sched', 'r') as sched:
+    with open('/proc/1/sched', 'r', encoding="utf-8") as sched:
         data_sched = sched.readline()
 
-    with open('/proc/self/cgroup', 'r') as cgroup:
+    with open('/proc/self/cgroup', 'r', encoding="utf-8") as cgroup:
         data_cgroup = cgroup.readline()
 
     checks = [
diff --git a/tests/test_options.py b/tests/test_options.py
index da1866f8..6fbe59f2 100644
--- a/tests/test_options.py
+++ b/tests/test_options.py
@@ -28,7 +28,7 @@ def test_options_merge(mock_parse, mock_run, mock_service):
     mock_parse.return_value = options
     fd, config_path = tempfile.mkstemp()
     os.close(fd)
-    with open(config_path, "w") as fd:
+    with open(config_path, "w", encoding="utf-8") as fd:
         fd.write('[default]\n')
         fd.write('output_type=human\n')
         fd.write('indent=5\n')
diff --git a/tests/test_suppress.py b/tests/test_suppress.py
index 18dc706c..27a3c715 100644
--- a/tests/test_suppress.py
+++ b/tests/test_suppress.py
@@ -76,7 +76,7 @@ def test_suppress_none(mock_find, mock_parse, mock_service):
 
     fd, config_path = tempfile.mkstemp()
     os.close(fd)
-    with open(config_path, "w") as fd:
+    with open(config_path, "w", encoding="utf-8") as fd:
         fd.write('[default]\n')
 
     try:
@@ -104,7 +104,7 @@ def test_suppress_source(mock_find, mock_parse, mock_service):
 
     fd, config_path = tempfile.mkstemp()
     os.close(fd)
-    with open(config_path, "w") as fd:
+    with open(config_path, "w", encoding="utf-8") as fd:
         fd.write('[default]\n')
         fd.write('[excludes]\n')
         fd.write('source=test_suppress\n')
@@ -134,7 +134,7 @@ def test_suppress_check(mock_find, mock_parse, mock_service):
 
     fd, config_path = tempfile.mkstemp()
     os.close(fd)
-    with open(config_path, "w") as fd:
+    with open(config_path, "w", encoding="utf-8") as fd:
         fd.write('[default]\n')
         fd.write('[excludes]\n')
         fd.write('check=PluginOne\n')
@@ -166,7 +166,7 @@ def test_suppress_key(mock_find, mock_parse, mock_service):
 
     fd, config_path = tempfile.mkstemp()
     os.close(fd)
-    with open(config_path, "w") as fd:
+    with open(config_path, "w", encoding="utf-8") as fd:
         fd.write('[default]\n')
         fd.write('[excludes]\n')
         fd.write('key=test2\n')