diff --git a/dbms/src/Common/FileChecker.cpp b/dbms/src/Common/FileChecker.cpp
index e3b1db745ca..bd8e00e38c0 100644
--- a/dbms/src/Common/FileChecker.cpp
+++ b/dbms/src/Common/FileChecker.cpp
@@ -95,13 +95,14 @@ void FileChecker::save() const
         /// So complex JSON structure - for compatibility with the old format.
         writeCString("{\"yandex\":{", out);
 
+        auto settings = FormatSettings();
         for (auto it = map.begin(); it != map.end(); ++it)
         {
             if (it != map.begin())
                 writeString(",", out);
 
             /// `escapeForFileName` is not really needed. But it is left for compatibility with the old code.
-            writeJSONString(escapeForFileName(it->first), out);
+            writeJSONString(escapeForFileName(it->first), out, settings);
             writeString(":{\"size\":\"", out);
             writeIntText(it->second, out);
             writeString("\"}", out);
diff --git a/dbms/src/Formats/JSONRowOutputStream.cpp b/dbms/src/Formats/JSONRowOutputStream.cpp
index 799564ddb04..89f57669a3e 100644
--- a/dbms/src/Formats/JSONRowOutputStream.cpp
+++ b/dbms/src/Formats/JSONRowOutputStream.cpp
@@ -50,7 +50,7 @@ void JSONRowOutputStream::writePrefix()
         writeString(fields[i].name, *ostr);
         writeCString(",\n", *ostr);
         writeCString("\t\t\t\"type\": ", *ostr);
-        writeJSONString(fields[i].type->getName(), *ostr);
+        writeJSONString(fields[i].type->getName(), *ostr, settings);
         writeChar('\n', *ostr);
 
         writeCString("\t\t}", *ostr);
@@ -149,7 +149,7 @@ void JSONRowOutputStream::writeTotals()
                 writeCString(",\n", *ostr);
 
             writeCString("\t\t", *ostr);
-            writeJSONString(column.name, *ostr);
+            writeJSONString(column.name, *ostr, settings);
             writeCString(": ", *ostr);
             column.type->serializeTextJSON(*column.column.get(), 0, *ostr, settings);
         }
diff --git a/dbms/src/IO/WriteHelpers.h b/dbms/src/IO/WriteHelpers.h
index 96d028faa81..932b0744d0c 100644
--- a/dbms/src/IO/WriteHelpers.h
+++ b/dbms/src/IO/WriteHelpers.h
@@ -174,7 +174,7 @@ inline void writeString(const StringRef & ref, WriteBuffer & buf)
  *  - it is assumed that string is in UTF-8, the invalid UTF-8 is not processed
  *  - all other non-ASCII characters remain as is
  */
-inline void writeJSONString(const char * begin, const char * end, WriteBuffer & buf, const FormatSettings & settings = FormatSettings())
+inline void writeJSONString(const char * begin, const char * end, WriteBuffer & buf, const FormatSettings & settings)
 {
     writeChar('"', buf);
     for (const char * it = begin; it != end; ++it)
@@ -313,13 +313,13 @@ void writeAnyEscapedString(const char * begin, const char * end, WriteBuffer & b
 }
 
 
-inline void writeJSONString(const String & s, WriteBuffer & buf, const FormatSettings & settings = FormatSettings())
+inline void writeJSONString(const String & s, WriteBuffer & buf, const FormatSettings & settings)
 {
     writeJSONString(s.data(), s.data() + s.size(), buf, settings);
 }
 
 
-inline void writeJSONString(const StringRef & ref, WriteBuffer & buf, const FormatSettings & settings = FormatSettings())
+inline void writeJSONString(const StringRef & ref, WriteBuffer & buf, const FormatSettings & settings)
 {
     writeJSONString(ref.data, ref.data + ref.size, buf, settings);
 }
diff --git a/dbms/tests/queries/0_stateless/00685_output_format_json_escape_forward_slashes.reference b/dbms/tests/queries/0_stateless/00685_output_format_json_escape_forward_slashes.reference
new file mode 100644
index 00000000000..d415e95f350
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00685_output_format_json_escape_forward_slashes.reference
@@ -0,0 +1,2 @@
+{"url":"\/some\/cool\/url"}
+{"url":"/some/cool/url"}
diff --git a/dbms/tests/queries/0_stateless/00685_output_format_json_escape_forward_slashes.sql b/dbms/tests/queries/0_stateless/00685_output_format_json_escape_forward_slashes.sql
new file mode 100644
index 00000000000..9842b07a8b0
--- /dev/null
+++ b/dbms/tests/queries/0_stateless/00685_output_format_json_escape_forward_slashes.sql
@@ -0,0 +1,5 @@
+SET output_format_json_escape_forward_slashes = 1;
+select '/some/cool/url' as url format JSONEachRow;
+SET output_format_json_escape_forward_slashes = 0;
+select '/some/cool/url' as url format JSONEachRow;
+SET output_format_json_escape_forward_slashes = 1;