diff --git a/make/compiler_flags b/make/compiler_flags
index 33295628e7c..a8c6eed1262 100644
--- a/make/compiler_flags
+++ b/make/compiler_flags
@@ -161,8 +161,19 @@ ifeq ($(OS),Windows_NT)
     CXXFLAGS_OS ?= -m64
   endif
 
-  UCRT_STRING := $(shell echo "\#include <windows.h>" | $(CXX) -E -dM -  | grep -i _UCRT)
-  ifneq (,$(UCRT_STRING))
+  ifeq (,$(wildcard $(MATH)make/ucrt))
+    UCRT_STRING := $(shell echo "#include <windows.h>" | $(CXX) -E -dM -  | findstr _UCRT)
+    ifneq (,$(UCRT_STRING))
+      IS_UCRT ?= true
+    else
+      IS_UCRT ?= false
+    endif
+    $(shell echo "IS_UCRT ?= $(IS_UCRT)" > $(MATH)make/ucrt)
+  else
+    -include $(MATH)make/ucrt
+  endif
+
+  ifeq ($(IS_UCRT),true)
     CXXFLAGS_OS += -D_UCRT
   endif
 
diff --git a/make/libraries b/make/libraries
index 1e28b44ea66..7dd5dcbfd45 100644
--- a/make/libraries
+++ b/make/libraries
@@ -140,7 +140,7 @@ ifeq (Linux, $(OS))
 endif
 
 ifeq (Windows_NT, $(OS))
-  ifneq (,$(UCRT_STRING))
+  ifeq ($(IS_UCRT),true)
     TBB_CXXFLAGS += -D_UCRT
   endif
 endif
diff --git a/makefile b/makefile
index f34da7b164b..f14ab40df4e 100644
--- a/makefile
+++ b/makefile
@@ -125,6 +125,7 @@ clean-deps:
 	@$(RM) $(call findfiles,test,*.d.*)
 	@$(RM) $(call findfiles,lib,*.d.*)
 	@$(RM) $(call findfiles,stan,*.dSYM)
+	@$(RM) $(call findfiles,make,ucrt)
 
 clean-all: clean clean-doxygen clean-deps clean-libraries