diff --git a/http/http_client.hpp b/http/http_client.hpp
index ab20eb0..53040ae 100644
--- a/http/http_client.hpp
+++ b/http/http_client.hpp
@@ -68,7 +68,6 @@
     std::optional<
         boost::beast::http::response_parser<boost::beast::http::string_body>>
         parser;
-    std::vector<std::pair<std::string, std::string>> headers;
     boost::circular_buffer_space_optimized<std::string> requestDataQueue{};
 
     ConnState state;
@@ -141,11 +140,6 @@
         req.target(uri);
         req.method(boost::beast::http::verb::post);
 
-        // Set headers
-        for (const auto& [key, value] : headers)
-        {
-            req.set(key, value);
-        }
         req.set(boost::beast::http::field::host, host);
         req.keep_alive(true);
 
@@ -425,10 +419,9 @@
         return;
     }
 
-    void setHeaders(
-        const std::vector<std::pair<std::string, std::string>>& httpHeaders)
+    void setHeaders(const boost::beast::http::fields& httpHeaders)
     {
-        headers = httpHeaders;
+        req.base() = boost::beast::http::header<true>(httpHeaders);
     }
 
     void setRetryConfig(const uint32_t retryAttempts,
diff --git a/include/event_service_store.hpp b/include/event_service_store.hpp
index 345b690..dcc99f1 100644
--- a/include/event_service_store.hpp
+++ b/include/event_service_store.hpp
@@ -1,6 +1,7 @@
 #pragma once
 #include "logging.hpp"
 
+#include <boost/beast/http/fields.hpp>
 #include <boost/container/flat_map.hpp>
 #include <nlohmann/json.hpp>
 
@@ -19,7 +20,7 @@
     std::vector<std::string> registryMsgIds;
     std::vector<std::string> registryPrefixes;
     std::vector<std::string> resourceTypes;
-    std::vector<nlohmann::json> httpHeaders; // key-value pair
+    boost::beast::http::fields httpHeaders;
     std::vector<std::string> metricReportDefinitions;
 
     static std::shared_ptr<UserSubscription>
@@ -146,13 +147,15 @@
                 const auto& obj = element.value();
                 for (const auto& val : obj.items())
                 {
-                    const auto value =
-                        val.value().get_ptr<const nlohmann::json::object_t*>();
+                    const std::string* value =
+                        val.value().get_ptr<const std::string*>();
                     if (value == nullptr)
                     {
+                        BMCWEB_LOG_ERROR << "Failed to parse value for key"
+                                         << val.key();
                         continue;
                     }
-                    subvalue->httpHeaders.emplace_back(*value);
+                    subvalue->httpHeaders.set(val.key(), *value);
                 }
             }
             else if (element.key() == "MetricReportDefinitions")
diff --git a/include/persistent_data.hpp b/include/persistent_data.hpp
index 4178d7d..d7230cb 100644
--- a/include/persistent_data.hpp
+++ b/include/persistent_data.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <app.hpp>
+#include <boost/beast/http/fields.hpp>
 #include <boost/container/flat_map.hpp>
 #include <boost/uuid/uuid.hpp>
 #include <boost/uuid/uuid_generators.hpp>
@@ -253,20 +254,31 @@
                     << "The subscription type is SSE, so skipping.";
                 continue;
             }
+            nlohmann::json::object_t headers;
+            for (const boost::beast::http::fields::value_type& header :
+                 subValue->httpHeaders)
+            {
+                // Note, these are technically copies because nlohmann doesn't
+                // support key lookup by std::string_view.  At least the
+                // following code can use move
+                // https://github.com/nlohmann/json/issues/1529
+                std::string name(header.name_string());
+                headers[std::move(name)] = header.value();
+            }
+
             subscriptions.push_back({
                 {"Id", subValue->id},
                 {"Context", subValue->customText},
                 {"DeliveryRetryPolicy", subValue->retryPolicy},
                 {"Destination", subValue->destinationUrl},
                 {"EventFormatType", subValue->eventFormatType},
-                {"HttpHeaders", subValue->httpHeaders},
+                {"HttpHeaders", std::move(headers)},
                 {"MessageIds", subValue->registryMsgIds},
                 {"Protocol", subValue->protocol},
                 {"RegistryPrefixes", subValue->registryPrefixes},
                 {"ResourceTypes", subValue->resourceTypes},
                 {"SubscriptionType", subValue->subscriptionType},
                 {"MetricReportDefinitions", subValue->metricReportDefinitions},
-
             });
         }
         persistentFile << data;
diff --git a/redfish-core/include/event_service_manager.hpp b/redfish-core/include/event_service_manager.hpp
index 3f398d7..079b28a 100644
--- a/redfish-core/include/event_service_manager.hpp
+++ b/redfish-core/include/event_service_manager.hpp
@@ -400,17 +400,7 @@
     {
         if (conn != nullptr)
         {
-            std::vector<std::pair<std::string, std::string>> reqHeaders;
-            for (const auto& header : httpHeaders)
-            {
-                for (const auto& item : header.items())
-                {
-                    std::string key = item.key();
-                    std::string val = item.value();
-                    reqHeaders.emplace_back(std::pair(key, val));
-                }
-            }
-            conn->setHeaders(reqHeaders);
+            conn->setHeaders(httpHeaders);
             conn->sendData(msg);
             this->eventSeqNum++;
         }
diff --git a/redfish-core/lib/event_service.hpp b/redfish-core/lib/event_service.hpp
index 8609862..b802280 100644
--- a/redfish-core/lib/event_service.hpp
+++ b/redfish-core/lib/event_service.hpp
@@ -17,6 +17,7 @@
 #include "event_service_manager.hpp"
 
 #include <app.hpp>
+#include <boost/beast/http/fields.hpp>
 #include <registries/privilege_registry.hpp>
 
 namespace redfish
@@ -343,7 +344,22 @@
 
                 if (headers)
                 {
-                    subValue->httpHeaders = *headers;
+                    for (const nlohmann::json& headerChunk : *headers)
+                    {
+                        for (const auto& item : headerChunk.items())
+                        {
+                            const std::string* value =
+                                item.value().get_ptr<const std::string*>();
+                            if (value == nullptr)
+                            {
+                                messages::propertyValueFormatError(
+                                    asyncResp->res, item.value().dump(2, true),
+                                    "HttpHeaders/" + item.key());
+                                return;
+                            }
+                            subValue->httpHeaders.set(item.key(), *value);
+                        }
+                    }
                 }
 
                 if (regPrefixes)
@@ -577,7 +593,25 @@
 
                 if (headers)
                 {
-                    subValue->httpHeaders = *headers;
+                    boost::beast::http::fields fields;
+                    for (const nlohmann::json& headerChunk : *headers)
+                    {
+                        for (auto& it : headerChunk.items())
+                        {
+                            const std::string* value =
+                                it.value().get_ptr<const std::string*>();
+                            if (value == nullptr)
+                            {
+                                messages::propertyValueFormatError(
+                                    asyncResp->res,
+                                    it.value().dump(2, ' ', true),
+                                    "HttpHeaders/" + it.key());
+                                return;
+                            }
+                            fields.set(it.key(), *value);
+                        }
+                    }
+                    subValue->httpHeaders = fields;
                 }
 
                 if (retryPolicy)