diff --git a/src/blockfilter.h b/src/blockfilter.h
--- a/src/blockfilter.h
+++ b/src/blockfilter.h
@@ -13,6 +13,7 @@
 #include <util/bytevectorhash.h>
 
 #include <cstdint>
+#include <set>
 #include <string>
 #include <unordered_set>
 #include <vector>
@@ -98,7 +99,7 @@
                            BlockFilterType &filter_type);
 
 /** Get a list of known filter types. */
-const std::vector<BlockFilterType> &AllBlockFilterTypes();
+const std::set<BlockFilterType> &AllBlockFilterTypes();
 
 /** Get a comma-separated list of known filter type names. */
 const std::string &ListBlockFilterTypes();
diff --git a/src/blockfilter.cpp b/src/blockfilter.cpp
--- a/src/blockfilter.cpp
+++ b/src/blockfilter.cpp
@@ -219,14 +219,13 @@
     return false;
 }
 
-const std::vector<BlockFilterType> &AllBlockFilterTypes() {
-    static std::vector<BlockFilterType> types;
+const std::set<BlockFilterType> &AllBlockFilterTypes() {
+    static std::set<BlockFilterType> types;
 
     static std::once_flag flag;
     std::call_once(flag, []() {
-        types.reserve(g_filter_types.size());
         for (auto entry : g_filter_types) {
-            types.push_back(entry.first);
+            types.insert(entry.first);
         }
     });
 
diff --git a/src/init.cpp b/src/init.cpp
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -82,6 +82,7 @@
 #endif
 #include <cstdint>
 #include <cstdio>
+#include <set>
 
 static const bool DEFAULT_PROXYRANDOMIZE = true;
 static const bool DEFAULT_REST_ENABLE = false;
@@ -1572,7 +1573,7 @@
 int nFD;
 ServiceFlags nLocalServices = ServiceFlags(NODE_NETWORK | NODE_NETWORK_LIMITED);
 int64_t peer_connect_timeout;
-std::vector<BlockFilterType> g_enabled_filter_types;
+std::set<BlockFilterType> g_enabled_filter_types;
 
 } // namespace
 
@@ -1667,14 +1668,13 @@
     } else if (blockfilterindex_value != "0") {
         const std::vector<std::string> names =
             gArgs.GetArgs("-blockfilterindex");
-        g_enabled_filter_types.reserve(names.size());
         for (const auto &name : names) {
             BlockFilterType filter_type;
             if (!BlockFilterTypeByName(name, filter_type)) {
                 return InitError(
                     strprintf(_("Unknown -blockfilterindex value %s."), name));
             }
-            g_enabled_filter_types.push_back(filter_type);
+            g_enabled_filter_types.insert(filter_type);
         }
     }