diff --git a/tests/src/unit-unicode2.cpp b/tests/src/unit-unicode2.cpp
index 02eab6f95..290bbff94 100644
--- a/tests/src/unit-unicode2.cpp
+++ b/tests/src/unit-unicode2.cpp
@@ -123,7 +123,7 @@ void check_utf8string(bool success_expected, int byte1, int byte2 = -1, int byte
 {
     if (++calls % 100000 == 0)
     {
-        std::cout << calls << " of 455355 UTF-8 strings checked" << std::endl;
+        std::cout << calls << " of 455355 UTF-8 strings checked" << std::endl; // NOLINT(performance-avoid-endl)
     }
 
     static std::string json_string;
diff --git a/tests/src/unit-unicode3.cpp b/tests/src/unit-unicode3.cpp
index 80cff40ad..396081108 100644
--- a/tests/src/unit-unicode3.cpp
+++ b/tests/src/unit-unicode3.cpp
@@ -123,7 +123,7 @@ void check_utf8string(bool success_expected, int byte1, int byte2 = -1, int byte
 {
     if (++calls % 100000 == 0)
     {
-        std::cout << calls << " of 1641521 UTF-8 strings checked" << std::endl;
+        std::cout << calls << " of 1641521 UTF-8 strings checked" << std::endl; // NOLINT(performance-avoid-endl)
     }
 
     static std::string json_string;
diff --git a/tests/src/unit-unicode4.cpp b/tests/src/unit-unicode4.cpp
index 6992b3123..966a241e0 100644
--- a/tests/src/unit-unicode4.cpp
+++ b/tests/src/unit-unicode4.cpp
@@ -123,7 +123,7 @@ void check_utf8string(bool success_expected, int byte1, int byte2 = -1, int byte
 {
     if (++calls % 100000 == 0)
     {
-        std::cout << calls << " of 5517507 UTF-8 strings checked" << std::endl;
+        std::cout << calls << " of 5517507 UTF-8 strings checked" << std::endl; // NOLINT(performance-avoid-endl)
     }
 
     static std::string json_string;
diff --git a/tests/src/unit-unicode5.cpp b/tests/src/unit-unicode5.cpp
index be12f3ae3..c75f76701 100644
--- a/tests/src/unit-unicode5.cpp
+++ b/tests/src/unit-unicode5.cpp
@@ -123,7 +123,7 @@ void check_utf8string(bool success_expected, int byte1, int byte2 = -1, int byte
 {
     if (++calls % 100000 == 0)
     {
-        std::cout << calls << " of 1246225 UTF-8 strings checked" << std::endl;
+        std::cout << calls << " of 1246225 UTF-8 strings checked" << std::endl; // NOLINT(performance-avoid-endl)
     }
 
     static std::string json_string;