diff --git a/icu4c/source/common/nameprep.cpp b/icu4c/source/common/nameprep.cpp
index 3a574a564c..e271a84147 100644
--- a/icu4c/source/common/nameprep.cpp
+++ b/icu4c/source/common/nameprep.cpp
@@ -22,8 +22,6 @@
 // *****************************************************************************
 // class NamePrep
 // *****************************************************************************
-static const UChar ASCII_SPACE = 0x0020;
-
 
 U_NAMESPACE_BEGIN
 
@@ -35,10 +33,6 @@ NamePrep::NamePrep(UErrorCode& status){
     doNFKC = TRUE;
 }
 
-UBool NamePrep::isNotProhibited(UChar32 ch){ 
-    return (UBool)(ch == ASCII_SPACE); 
-}
-
 U_NAMESPACE_END
 
 #endif /* #if !UCONFIG_NO_IDNA */
diff --git a/icu4c/source/common/nameprep.h b/icu4c/source/common/nameprep.h
index 82b33abe0d..16f2676116 100644
--- a/icu4c/source/common/nameprep.h
+++ b/icu4c/source/common/nameprep.h
@@ -82,7 +82,11 @@ private:
     static const char fgClassID;
 };
 
+#define ASCII_SPACE 0x0020
 
+inline UBool NamePrep::isNotProhibited(UChar32 ch){
+    return (UBool)(ch == ASCII_SPACE);
+}
 
 U_NAMESPACE_END