diff --git a/src/types.cpp b/src/types.cpp
index 0d20d7d..8467b76 100644
--- a/src/types.cpp
+++ b/src/types.cpp
@@ -2,8 +2,6 @@
 
 #include <fmt/format.h>
 
-#include <charconv>
-
 void phosphor::network::IfAddr::invalidPfx(uint8_t pfx)
 {
     throw std::invalid_argument(fmt::format("Invalid prefix {}", pfx));
diff --git a/src/util.cpp b/src/util.cpp
index 23c642f..675409f 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -10,7 +10,6 @@
 #include <sys/wait.h>
 
 #include <cctype>
-#include <charconv>
 #include <phosphor-logging/elog-errors.hpp>
 #include <phosphor-logging/log.hpp>
 #include <string>
@@ -133,10 +132,12 @@
         return std::nullopt;
     }
     intf.remove_prefix(pfx.size());
-    auto last = intf.data() + intf.size();
-    unsigned long idx;
-    auto res = std::from_chars(intf.data(), last, idx);
-    if (res.ec != std::errc() || res.ptr != last)
+    unsigned idx;
+    try
+    {
+        idx = DecodeInt<unsigned, 10>{}(intf);
+    }
+    catch (...)
     {
         return std::nullopt;
     }
diff --git a/test/test_util.cpp b/test/test_util.cpp
index 3978b1e..8ad2136 100644
--- a/test/test_util.cpp
+++ b/test/test_util.cpp
@@ -4,7 +4,6 @@
 #include <fmt/chrono.h>
 #include <netinet/in.h>
 
-#include <charconv>
 #include <cstddef>
 #include <cstring>
 #include <stdexcept>