diff --git a/src/NzbDrone.Api.Test/Sonarr.Api.Test.csproj b/src/NzbDrone.Api.Test/Sonarr.Api.Test.csproj
index 12a3c40f5..88f16cc3a 100644
--- a/src/NzbDrone.Api.Test/Sonarr.Api.Test.csproj
+++ b/src/NzbDrone.Api.Test/Sonarr.Api.Test.csproj
@@ -9,6 +9,7 @@
   <ItemGroup>
     <ProjectReference Include="..\NzbDrone.Core\Sonarr.Core.csproj" />
     <ProjectReference Include="..\NzbDrone.Test.Common\Sonarr.Test.Common.csproj" />
+    <ProjectReference Include="..\Sonarr.Api.V3\Sonarr.Api.V3.csproj" />
     <ProjectReference Include="..\Sonarr.Http\Sonarr.Http.csproj" />
   </ItemGroup>
 </Project>
diff --git a/src/NzbDrone.Api.Test/v3/ReleaseProfiles/ReleaseProfilesFixture.cs b/src/NzbDrone.Api.Test/v3/ReleaseProfiles/ReleaseProfilesFixture.cs
new file mode 100644
index 000000000..916f0387e
--- /dev/null
+++ b/src/NzbDrone.Api.Test/v3/ReleaseProfiles/ReleaseProfilesFixture.cs
@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using FluentAssertions;
+using NUnit.Framework;
+using NzbDrone.Common.Serializer;
+using Sonarr.Api.V3.Profiles.Release;
+using Sonarr.Http.REST;
+
+namespace NzbDrone.Api.Test.v3.ReleaseProfiles
+{
+    [TestFixture]
+    public class ReleaseProfilesFixture
+    {
+        [Test]
+        public void should_deserialize_releaseprofile_v3_ignored_null()
+        {
+            var resource = Json.Deserialize<ReleaseProfileResource>("{ \"ignored\": null, \"required\": null }");
+
+            var model = resource.ToModel();
+
+            model.Ignored.Should().BeEquivalentTo();
+            model.Required.Should().BeEquivalentTo();
+        }
+
+        [Test]
+        public void should_deserialize_releaseprofile_v3_ignored_string()
+        {
+            var resource = Json.Deserialize<ReleaseProfileResource>("{ \"ignored\": \"testa,testb\", \"required\": \"testc,testd\" }");
+
+            var model = resource.ToModel();
+
+            model.Ignored.Should().BeEquivalentTo("testa", "testb");
+            model.Required.Should().BeEquivalentTo("testc", "testd");
+        }
+
+        [Test]
+        public void should_deserialize_releaseprofile_v3_ignored_string_array()
+        {
+            var resource = Json.Deserialize<ReleaseProfileResource>("{ \"ignored\": [ \"testa\", \"testb\" ], \"required\": [ \"testc\", \"testd\" ] }");
+
+            var model = resource.ToModel();
+
+            model.Ignored.Should().BeEquivalentTo("testa", "testb");
+            model.Required.Should().BeEquivalentTo("testc", "testd");
+        }
+
+        [Test]
+        public void should_throw_with_bad_releaseprofile_v3_ignored_type()
+        {
+            var resource = Json.Deserialize<ReleaseProfileResource>("{ \"ignored\": {} }");
+
+            Assert.Throws<BadRequestException>(() => resource.ToModel());
+        }
+    }
+}
diff --git a/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileModule.cs b/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileModule.cs
index d3fed8e8a..1248e697f 100644
--- a/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileModule.cs
+++ b/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileModule.cs
@@ -27,7 +27,7 @@ namespace Sonarr.Api.V3.Profiles.Release
 
             SharedValidator.RuleFor(d => d).Custom((restriction, context) =>
             {
-                if (restriction.Ignored.Empty() && restriction.Required.Empty() && restriction.Preferred.Empty())
+                if (restriction.MapIgnored().Empty() && restriction.MapRequired().Empty() && restriction.Preferred.Empty())
                 {
                     context.AddFailure("'Must contain', 'Must not contain' or 'Preferred' is required");
                 }
diff --git a/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileResource.cs b/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileResource.cs
index 7ac876a53..1029dfbd7 100644
--- a/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileResource.cs
+++ b/src/Sonarr.Api.V3/Profiles/Release/ReleaseProfileResource.cs
@@ -1,5 +1,8 @@
+using System;
 using System.Collections.Generic;
 using System.Linq;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
 using NzbDrone.Core.Profiles.Releases;
 using Sonarr.Http.REST;
 
@@ -9,8 +12,9 @@ namespace Sonarr.Api.V3.Profiles.Release
     {
         public string Name { get; set; }
         public bool Enabled { get; set; }
-        public List<string> Required { get; set; }
-        public List<string> Ignored { get; set; }
+        // Is List<string>, string or JArray, we accept 'string' with POST for backward compatibility
+        public object Required { get; set; }
+        public object Ignored { get; set; }
         public List<KeyValuePair<string, int>> Preferred { get; set; }
         public bool IncludePreferredWhenRenaming { get; set; }
         public int IndexerId { get; set; }
@@ -18,8 +22,6 @@ namespace Sonarr.Api.V3.Profiles.Release
 
         public ReleaseProfileResource()
         {
-            Required = new List<string>();
-            Ignored = new List<string>();
             Preferred = new List<KeyValuePair<string, int>>();
             Tags = new HashSet<int>();
         }
@@ -36,8 +38,8 @@ namespace Sonarr.Api.V3.Profiles.Release
                 Id = model.Id,
                 Name = model.Name,
                 Enabled = model.Enabled,
-                Required = model.Required,
-                Ignored = model.Ignored,
+                Required = model.Required ?? new List<string>(),
+                Ignored = model.Ignored ?? new List<string>(),
                 Preferred = model.Preferred,
                 IncludePreferredWhenRenaming = model.IncludePreferredWhenRenaming,
                 IndexerId = model.IndexerId,
@@ -54,8 +56,8 @@ namespace Sonarr.Api.V3.Profiles.Release
                 Id = resource.Id,
                 Name = resource.Name,
                 Enabled = resource.Enabled,
-                Required = resource.Required,
-                Ignored = resource.Ignored,
+                Required = resource.MapRequired(),
+                Ignored = resource.MapIgnored(),
                 Preferred = resource.Preferred,
                 IncludePreferredWhenRenaming = resource.IncludePreferredWhenRenaming,
                 IndexerId = resource.IndexerId,
@@ -67,5 +69,33 @@ namespace Sonarr.Api.V3.Profiles.Release
         {
             return models.Select(ToResource).ToList();
         }
+
+        public static List<string> MapRequired(this ReleaseProfileResource profile) => ParseArray(profile.Required, "required");
+        public static List<string> MapIgnored(this ReleaseProfileResource profile) => ParseArray(profile.Ignored, "ignored");
+        
+        private static List<string> ParseArray(object resource, string title)
+        {
+            if (resource == null)
+            {
+                return new List<string>();
+            }
+
+            if (resource is List<string> list)
+            {
+                return list;
+            }
+
+            if (resource is JArray jarray)
+            {
+                return jarray.ToObject<List<string>>();
+            }
+
+            if (resource is string str)
+            {
+                return str.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries).ToList();
+            }
+
+            throw new BadRequestException($"Invalid field {title}, should be string or string array");
+        }
     }
 }