diff --git a/cores/esp8266/Esp.cpp b/cores/esp8266/Esp.cpp
index 42715605c1..3f7aca01b5 100644
--- a/cores/esp8266/Esp.cpp
+++ b/cores/esp8266/Esp.cpp
@@ -25,7 +25,7 @@
 #include "interrupts.h"
 #include "MD5Builder.h"
 #include "umm_malloc/umm_malloc.h"
-#include "cont.h"
+#include "coredecls.h"
 
 extern "C" {
 #include "user_interface.h"
@@ -574,3 +574,11 @@ String EspClass::getSketchMD5()
     result = md5.toString();
     return result;
 }
+
+void EspClass::setAutoFormatSPIFFS (bool autoFormat) {
+    _spiffsAutoFormat = autoFormat;
+}
+
+bool EspClass::getAutoFormatSPIFFS () {
+    return _spiffsAutoFormat;
+}
diff --git a/cores/esp8266/Esp.h b/cores/esp8266/Esp.h
index b2ee09144b..09ed49e199 100644
--- a/cores/esp8266/Esp.h
+++ b/cores/esp8266/Esp.h
@@ -153,6 +153,9 @@ class EspClass {
         bool eraseConfig();
 
         inline uint32_t getCycleCount();
+
+        bool getAutoFormatSPIFFS ();
+        void setAutoFormatSPIFFS (bool autoFormat);
 };
 
 uint32_t EspClass::getCycleCount()
diff --git a/cores/esp8266/coredecls.h b/cores/esp8266/coredecls.h
index 3ac87eee9f..ff7d02e075 100644
--- a/cores/esp8266/coredecls.h
+++ b/cores/esp8266/coredecls.h
@@ -12,6 +12,7 @@ extern "C" {
 #include <cont.h> // g_pcont declaration
 
 extern bool timeshift64_is_set;
+extern bool _spiffsAutoFormat;
 
 void esp_yield();
 void esp_schedule();
diff --git a/cores/esp8266/spiffs_api.cpp b/cores/esp8266/spiffs_api.cpp
index 390a6412fd..85ef8b3583 100644
--- a/cores/esp8266/spiffs_api.cpp
+++ b/cores/esp8266/spiffs_api.cpp
@@ -23,6 +23,8 @@
  */
 #include "spiffs_api.h"
 
+bool _spiffsAutoFormat = true;
+
 using namespace fs;
 
 FileImplPtr SPIFFSImpl::open(const char* path, OpenMode openMode, AccessMode accessMode)
diff --git a/cores/esp8266/spiffs_api.h b/cores/esp8266/spiffs_api.h
index 4ce8d3e6ba..7228af3970 100644
--- a/cores/esp8266/spiffs_api.h
+++ b/cores/esp8266/spiffs_api.h
@@ -32,6 +32,7 @@
 #include "spiffs/spiffs.h"
 #include "debug.h"
 #include "flash_utils.h"
+#include "coredecls.h" // _spiffsAutoFormat
 
 using namespace fs;
 
@@ -124,6 +125,9 @@ class SPIFFSImpl : public FSImpl
         if (_tryMount()) {
             return true;
         }
+        if (!_spiffsAutoFormat) {
+            return false;
+        }
         auto rc = SPIFFS_format(&_fs);
         if (rc != SPIFFS_OK) {
             DEBUGV("SPIFFS_format: rc=%d, err=%d\r\n", rc, _fs.err_code);
diff --git a/doc/filesystem.rst b/doc/filesystem.rst
index 3e6fdeffbf..3f975ab5ae 100644
--- a/doc/filesystem.rst
+++ b/doc/filesystem.rst
@@ -136,6 +136,10 @@ This method mounts SPIFFS file system. It must be called before any
 other FS APIs are used. Returns *true* if file system was mounted
 successfully, false otherwise.
 
+This will by default format filesystem when SPIFFS is used the first time. 
+Note that this can be disabled with a call to
+``ESP.setAutoFormatSPIFFS(false);`` prior to ``SPIFFS.begin()``.
+
 end
 ~~~
 
diff --git a/libraries/esp8266/keywords.txt b/libraries/esp8266/keywords.txt
index f6bb96b5d7..55c0303c9f 100644
--- a/libraries/esp8266/keywords.txt
+++ b/libraries/esp8266/keywords.txt
@@ -60,6 +60,8 @@ getResetInfo	KEYWORD2
 getResetInfoPtr	KEYWORD2
 eraseConfig	KEYWORD2
 getCycleCount	KEYWORD2
+setAutoFormatSPIFFS	KEYWORD2
+getAutoFormatSPIFFS	KEYWORD2
 
 #######################################
 # Constants (LITERAL1)