diff --git a/src/TypedRest.Reactive/Endpoints/Reactive/StreamingEndpoint.cs b/src/TypedRest.Reactive/Endpoints/Reactive/StreamingEndpoint.cs
index 3ae77554..a9e55fc0 100644
--- a/src/TypedRest.Reactive/Endpoints/Reactive/StreamingEndpoint.cs
+++ b/src/TypedRest.Reactive/Endpoints/Reactive/StreamingEndpoint.cs
@@ -47,7 +47,7 @@ public virtual IObservable<TEntity> GetObservable()
             using var response = await HttpClient.GetAsync(Uri, HttpCompletionOption.ResponseHeadersRead, cancellationToken);
             await ErrorHandler.HandleAsync(response);
 
-            var entityStream = new HttpEntityStream<TEntity>(response.Content, Serializers[0], _separator, BufferSize);
+            var entityStream = new HttpEntityStream<TEntity>(response.Content, Serializer, _separator, BufferSize);
 
             while (!cancellationToken.IsCancellationRequested)
             {
diff --git a/src/TypedRest/Endpoints/EndpointBase.cs b/src/TypedRest/Endpoints/EndpointBase.cs
index cc2ae308..d09f0f87 100644
--- a/src/TypedRest/Endpoints/EndpointBase.cs
+++ b/src/TypedRest/Endpoints/EndpointBase.cs
@@ -12,9 +12,21 @@ namespace TypedRest.Endpoints;
 public abstract class EndpointBase : IEndpoint
 {
     public Uri Uri { get; }
+
     public HttpClient HttpClient { get; }
+
     public IReadOnlyList<MediaTypeFormatter> Serializers { get; }
+
+    /// <summary>
+    /// The serializer used for entities sent to the server. Equal to the first entry in <see cref="Serializers"/>.
+    /// </summary>
+    /// <exception cref="InvalidOperationException"><see cref="Serializers"/> is empty.</exception>
+    protected virtual MediaTypeFormatter Serializer
+        => Serializers.FirstOrDefault()
+        ?? throw new InvalidOperationException($"{nameof(Serializers)} is empty.");
+
     public IErrorHandler ErrorHandler { get; }
+
     public ILinkExtractor LinkExtractor { get; }
 
     /// <summary>
diff --git a/src/TypedRest/Endpoints/Generic/CollectionEndpoint.cs b/src/TypedRest/Endpoints/Generic/CollectionEndpoint.cs
index f5aa765f..95f46d9b 100644
--- a/src/TypedRest/Endpoints/Generic/CollectionEndpoint.cs
+++ b/src/TypedRest/Endpoints/Generic/CollectionEndpoint.cs
@@ -109,7 +109,7 @@ public virtual async Task<PartialResponse<TEntity>> ReadRangeAsync(RangeItemHead
     {
         if (entity == null) throw new ArgumentNullException(nameof(entity));
 
-        var response = await HandleAsync(() => HttpClient.PostAsync(Uri, entity, Serializers[0], cancellationToken)).NoContext();
+        var response = await HandleAsync(() => HttpClient.PostAsync(Uri, entity, Serializer, cancellationToken)).NoContext();
 
         TElementEndpoint elementEndpoint;
         if (response.Headers.Location == null)
@@ -143,7 +143,7 @@ public virtual async Task CreateAllAsync(IEnumerable<TEntity> entities, Cancella
     {
         if (entities == null) throw new ArgumentNullException(nameof(entities));
 
-        await FinalizeAsync(() => HttpClient.PatchAsync(Uri, entities, Serializers[0], cancellationToken)).NoContext();
+        await FinalizeAsync(() => HttpClient.PatchAsync(Uri, entities, Serializer, cancellationToken)).NoContext();
     }
 
     public bool? SetAllAllowed => IsMethodAllowed(HttpMethod.Put);
@@ -152,7 +152,7 @@ public async Task SetAllAsync(IEnumerable<TEntity> entities, CancellationToken c
     {
         if (entities == null) throw new ArgumentNullException(nameof(entities));
 
-        using var content = new ObjectContent<IEnumerable<TEntity>>(entities, Serializers[0]);
+        using var content = new ObjectContent<IEnumerable<TEntity>>(entities, Serializer);
         (await PutContentAsync(content, cancellationToken)).Dispose();
     }
 }
diff --git a/src/TypedRest/Endpoints/Generic/ElementEndpoint.cs b/src/TypedRest/Endpoints/Generic/ElementEndpoint.cs
index aec5f2f9..a47b2a18 100644
--- a/src/TypedRest/Endpoints/Generic/ElementEndpoint.cs
+++ b/src/TypedRest/Endpoints/Generic/ElementEndpoint.cs
@@ -54,7 +54,7 @@ public async Task<bool> ExistsAsync(CancellationToken cancellationToken = defaul
     {
         if (entity == null) throw new ArgumentNullException(nameof(entity));
 
-        using var content = new ObjectContent<TEntity>(entity, Serializers[0]);
+        using var content = new ObjectContent<TEntity>(entity, Serializer);
         using var response = await PutContentAsync(content, cancellationToken);
         return await TryReadAsAsync(response, cancellationToken);
     }
@@ -65,7 +65,7 @@ public async Task<bool> ExistsAsync(CancellationToken cancellationToken = defaul
     {
         if (entity == null) throw new ArgumentNullException(nameof(entity));
 
-        using var response = await HandleAsync(() => HttpClient.PatchAsync(Uri, entity, Serializers[0], cancellationToken)).NoContext();
+        using var response = await HandleAsync(() => HttpClient.PatchAsync(Uri, entity, Serializer, cancellationToken)).NoContext();
         ResponseCache = null;
         return await TryReadAsAsync(response, cancellationToken);
     }
diff --git a/src/TypedRest/Endpoints/Rpc/ConsumerEndpoint.cs b/src/TypedRest/Endpoints/Rpc/ConsumerEndpoint.cs
index 9af7f022..e0b71726 100644
--- a/src/TypedRest/Endpoints/Rpc/ConsumerEndpoint.cs
+++ b/src/TypedRest/Endpoints/Rpc/ConsumerEndpoint.cs
@@ -28,6 +28,6 @@ public async Task InvokeAsync(TEntity entity, CancellationToken cancellationToke
     {
         if (entity == null) throw new ArgumentNullException(nameof(entity));
 
-        await FinalizeAsync(() => HttpClient.PostAsync(Uri, entity, Serializers[0], cancellationToken)).NoContext();
+        await FinalizeAsync(() => HttpClient.PostAsync(Uri, entity, Serializer, cancellationToken)).NoContext();
     }
 }
diff --git a/src/TypedRest/Endpoints/Rpc/FunctionEndpoint.cs b/src/TypedRest/Endpoints/Rpc/FunctionEndpoint.cs
index 7214f81b..af7dc829 100644
--- a/src/TypedRest/Endpoints/Rpc/FunctionEndpoint.cs
+++ b/src/TypedRest/Endpoints/Rpc/FunctionEndpoint.cs
@@ -29,7 +29,7 @@ public async Task<TResult> InvokeAsync(TEntity entity, CancellationToken cancell
     {
         if (entity == null) throw new ArgumentNullException(nameof(entity));
 
-        using var response = await HandleAsync(() => HttpClient.PostAsync(Uri, entity, Serializers[0], cancellationToken)).NoContext();
+        using var response = await HandleAsync(() => HttpClient.PostAsync(Uri, entity, Serializer, cancellationToken)).NoContext();
         return await response.Content.ReadAsAsync<TResult>(Serializers, cancellationToken).NoContext();
     }
 }