diff --git a/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/MultiInvoker.java b/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/MultiInvoker.java
index 9a0efc53b2909..11d1fe1693b6a 100644
--- a/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/MultiInvoker.java
+++ b/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/MultiInvoker.java
@@ -125,7 +125,9 @@ public <R> Multi<R> method(String name, Entity<?> entity, GenericType<R> respons
                     if (!emitter.isCancelled()) {
                         if (response.getStatus() == 200
                                 && MediaType.SERVER_SENT_EVENTS_TYPE.isCompatible(response.getMediaType())) {
-                            registerForSse(multiRequest, responseType, response, vertxResponse);
+                            registerForSse(multiRequest, responseType, response, vertxResponse,
+                                    (String) restClientRequestContext.getProperties()
+                                            .get(RestClientRequestContext.DEFAULT_CONTENT_TYPE_PROP));
                         } else if (response.getStatus() == 200
                                 && RestMediaType.APPLICATION_STREAM_JSON_TYPE.isCompatible(response.getMediaType())) {
                             registerForJsonStream(multiRequest, restClientRequestContext, responseType, response,
@@ -152,12 +154,12 @@ private boolean isNewlineDelimited(ResponseImpl response) {
     private <R> void registerForSse(MultiRequest<? super R> multiRequest,
             GenericType<R> responseType,
             Response response,
-            HttpClientResponse vertxResponse) {
+            HttpClientResponse vertxResponse, String defaultContentType) {
         // honestly, isn't reconnect contradictory with completion?
         // FIXME: Reconnect settings?
         // For now we don't want multi to reconnect
         SseEventSourceImpl sseSource = new SseEventSourceImpl(invocationBuilder.getTarget(),
-                invocationBuilder, Integer.MAX_VALUE, TimeUnit.SECONDS);
+                invocationBuilder, Integer.MAX_VALUE, TimeUnit.SECONDS, defaultContentType);
 
         multiRequest.onCancel(sseSource::close);
         sseSource.register(event -> {
diff --git a/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseEventSourceImpl.java b/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseEventSourceImpl.java
index 86ce7c526591c..fbdf2cc6ff5e5 100644
--- a/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseEventSourceImpl.java
+++ b/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseEventSourceImpl.java
@@ -42,6 +42,11 @@ public class SseEventSourceImpl implements SseEventSource, Handler<Long> {
 
     public SseEventSourceImpl(WebTargetImpl webTarget, Invocation.Builder invocationBuilder,
             long reconnectDelay, TimeUnit reconnectUnit) {
+        this(webTarget, invocationBuilder, reconnectDelay, reconnectUnit, null);
+    }
+
+    public SseEventSourceImpl(WebTargetImpl webTarget, Invocation.Builder invocationBuilder,
+            long reconnectDelay, TimeUnit reconnectUnit, String defaultContentType) {
         // tests set a null endpoint
         Objects.requireNonNull(reconnectUnit);
         if (reconnectDelay <= 0)
@@ -49,7 +54,7 @@ public SseEventSourceImpl(WebTargetImpl webTarget, Invocation.Builder invocation
         this.webTarget = webTarget;
         this.reconnectDelay = reconnectDelay;
         this.reconnectUnit = reconnectUnit;
-        this.sseParser = new SseParser(this);
+        this.sseParser = new SseParser(this, defaultContentType);
         this.invocationBuilder = invocationBuilder;
     }
 
@@ -136,7 +141,9 @@ private void registerOnClient(HttpClientResponse vertxClientResponse) {
         vertxClientResponse.request().exceptionHandler(null);
         connection = vertxClientResponse.request().connection();
         String sseContentTypeHeader = vertxClientResponse.getHeader(CommonSseUtil.SSE_CONTENT_TYPE);
-        sseParser.setSseContentTypeHeader(sseContentTypeHeader);
+        if ((sseContentTypeHeader != null) && !sseContentTypeHeader.isEmpty()) {
+            sseParser.setSseContentTypeHeader(sseContentTypeHeader);
+        }
         // we don't add a closeHandler handler on the connection as it can race with this handler
         // and close before the emitter emits anything
         // see: https://github.com/quarkusio/quarkus/pull/16438
diff --git a/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseParser.java b/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseParser.java
index 7728e87ff7098..08525139dc0e9 100644
--- a/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseParser.java
+++ b/independent-projects/resteasy-reactive/client/runtime/src/main/java/org/jboss/resteasy/reactive/client/impl/SseParser.java
@@ -50,7 +50,8 @@ public class SseParser implements Handler<Buffer> {
      */
     private String contentType;
     /**
-     * The content type we're reading. Defaults to the X-Sse-Element-Type header
+     * The content type we're reading. If the X-Sse-Element-Type header is not set, then it defaults to the declared @Produces
+     * (if any)
      */
     private String contentTypeHeader;
     /**
@@ -67,8 +68,9 @@ public class SseParser implements Handler<Buffer> {
     private long eventReconnectTime = SseEvent.RECONNECT_NOT_SET;
     private SseEventSourceImpl sseEventSource;
 
-    public SseParser(SseEventSourceImpl sseEventSource) {
+    public SseParser(SseEventSourceImpl sseEventSource, String defaultContentType) {
         this.sseEventSource = sseEventSource;
+        this.contentTypeHeader = defaultContentType;
     }
 
     public void setSseContentTypeHeader(String sseContentTypeHeader) {