diff --git a/src/netbase.cpp b/src/netbase.cpp
index 40be319045e..78995953e2a 100644
--- a/src/netbase.cpp
+++ b/src/netbase.cpp
@@ -24,7 +24,6 @@
 #include <fcntl.h>
 #endif
 
-#include <boost/algorithm/string/case_conv.hpp> // for to_lower()
 #include <boost/algorithm/string/predicate.hpp> // for startswith() and endswith()
 
 #if !defined(HAVE_MSG_NOSIGNAL) && !defined(MSG_NOSIGNAL)
@@ -43,7 +42,7 @@ static const int SOCKS5_RECV_TIMEOUT = 20 * 1000;
 static std::atomic<bool> interruptSocks5Recv(false);
 
 enum Network ParseNetwork(std::string net) {
-    boost::to_lower(net);
+    Downcase(net);
     if (net == "ipv4") return NET_IPV4;
     if (net == "ipv6") return NET_IPV6;
     if (net == "tor" || net == "onion")  return NET_TOR;
diff --git a/src/rpc/client.cpp b/src/rpc/client.cpp
index feca3d8fd65..17019ef0320 100644
--- a/src/rpc/client.cpp
+++ b/src/rpc/client.cpp
@@ -11,7 +11,6 @@
 #include <set>
 #include <stdint.h>
 
-#include <boost/algorithm/string/case_conv.hpp> // for to_lower()
 #include <univalue.h>
 
 using namespace std;
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
index 3122a5a45ef..3b97324e1fc 100644
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -20,7 +20,6 @@
 #include <boost/bind/bind.hpp>
 #include <boost/signals2/signal.hpp>
 #include <boost/thread.hpp>
-#include <boost/algorithm/string/case_conv.hpp> // for to_upper()
 
 #include <memory> // for unique_ptr
 #include <unordered_map>
@@ -230,7 +229,7 @@ std::string CRPCTable::help(const std::string& strCommand) const
                         strRet += "\n";
                     category = pcmd->category;
                     string firstLetter = category.substr(0,1);
-                    boost::to_upper(firstLetter);
+                    Capitalize(firstLetter);
                     strRet += "== " + firstLetter + category.substr(1) + " ==\n";
                 }
             }
diff --git a/src/util.cpp b/src/util.cpp
index b283f65f7d2..3e082a028cc 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -353,7 +353,7 @@ void ParseParameters(int argc, const char* const argv[])
             str = str.substr(0, is_index);
         }
 #ifdef WIN32
-        boost::to_lower(str);
+        Downcase(str);
         if (boost::algorithm::starts_with(str, "/"))
             str = "-" + str.substr(1);
 #endif