diff --git a/src/DfE.CoreLibs.Testing/AutoFixture/Customizations/DbContextCustomization.cs b/src/DfE.CoreLibs.Testing/AutoFixture/Customizations/DbContextCustomization.cs
deleted file mode 100644
index 1d7b566..0000000
--- a/src/DfE.CoreLibs.Testing/AutoFixture/Customizations/DbContextCustomization.cs
+++ /dev/null
@@ -1,31 +0,0 @@
-using AutoFixture;
-using DfE.CoreLibs.Testing.Helpers;
-using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.DependencyInjection;
-using System.Diagnostics.CodeAnalysis;
-
-namespace DfE.CoreLibs.Testing.AutoFixture.Customizations
-{
-    [ExcludeFromCodeCoverage]
-    public class DbContextCustomization<TContext> : ICustomization where TContext : DbContext
-    {
-        public void Customize(IFixture fixture)
-        {
-            fixture.Register<DbSet<object>>(() => null!);
-
-            fixture.Customize<TContext>(composer => composer.FromFactory(() =>
-            {
-                var services = new ServiceCollection();
-
-                DbContextHelper.CreateDbContext<TContext>(services);
-
-                var serviceProvider = services.BuildServiceProvider();
-                var dbContext = serviceProvider.GetRequiredService<TContext>();
-
-                fixture.Inject(dbContext);
-
-                return dbContext;
-            }).OmitAutoProperties());
-        }
-    }
-}
diff --git a/src/DfE.CoreLibs.Testing/Helpers/DbContextHelper.cs b/src/DfE.CoreLibs.Testing/Helpers/DbContextHelper.cs
index 4cdd4d0..22f432b 100644
--- a/src/DfE.CoreLibs.Testing/Helpers/DbContextHelper.cs
+++ b/src/DfE.CoreLibs.Testing/Helpers/DbContextHelper.cs
@@ -1,60 +1,53 @@
-using System.Data.Common;
-using System.Diagnostics.CodeAnalysis;
-using Microsoft.Data.Sqlite;
 using Microsoft.EntityFrameworkCore;
-using Microsoft.Extensions.Configuration;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage;
 using Microsoft.Extensions.DependencyInjection;
+using System.Data.Common;
+using System.Diagnostics.CodeAnalysis;
 
 namespace DfE.CoreLibs.Testing.Helpers
 {
     [ExcludeFromCodeCoverage]
     public static class DbContextHelper
     {
-        public static void CreateDbContext<TContext>(IServiceCollection services, Action<TContext>? seedTestData = null) where TContext : DbContext
+        public static void CreateDbContext<TContext>(
+            IServiceCollection services,
+            DbConnection connection,
+            Action<TContext>? seedTestData = null) where TContext : DbContext
         {
-            var connectionString = GetConnectionStringFromConfig();
+            ConfigureDbContext<TContext>(services, connection);
+            InitializeDbContext(services, seedTestData);
+        }
 
-            if (string.IsNullOrEmpty(connectionString) || connectionString.Contains("DataSource=:memory:"))
+        public static void ConfigureDbContext<TContext>(
+            IServiceCollection services,
+            DbConnection connection) where TContext : DbContext
+        {
+            services.AddDbContext<TContext>((sp, options) =>
             {
-                // Sqlite doesn't seem to allow multiple dbContexts added to the same connection
-                // We are creating a separate in-memory database for each dbContext
-                // Please feel free to update if you have a better/ more efficient solution
-                var connection = new SqliteConnection("DataSource=:memory:");
-
-                connection.Open();
+                options.UseSqlite(connection);
+            });
+        }
 
-                services.AddSingleton(connection);
+        private static void InitializeDbContext<TContext>(
+            IServiceCollection services,
+            Action<TContext>? seedTestData) where TContext : DbContext
+        {
+            var serviceProvider = services.BuildServiceProvider();
+            using var scope = serviceProvider.CreateScope();
+            var dbContext = scope.ServiceProvider.GetRequiredService<TContext>();
 
-                services.AddDbContext<TContext>((sp, options) =>
-                {
-                    options.UseSqlite(connection);
-                });
+            var relationalDatabaseCreator = dbContext.Database.GetService<IRelationalDatabaseCreator>();
+            if (!dbContext.Database.CanConnect())
+            {
+                relationalDatabaseCreator.Create();
             }
             else
             {
-                services.AddDbContext<TContext>(options =>
-                {
-                    options.UseSqlServer(connectionString);
-                });
+                relationalDatabaseCreator.CreateTables();
             }
 
-            var serviceProvider = services.BuildServiceProvider();
-
-            using var scope = serviceProvider.CreateScope();
-            var dbContext = scope.ServiceProvider.GetRequiredService<TContext>();
-            dbContext.Database.EnsureCreated();
-
             seedTestData?.Invoke(dbContext);
         }
-
-        private static string? GetConnectionStringFromConfig()
-        {
-            var configuration = new ConfigurationBuilder()
-                .SetBasePath(Directory.GetCurrentDirectory())
-                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
-                .Build();
-
-            return configuration.GetConnectionString("DefaultConnection");
-        }
     }
-}
+}
\ No newline at end of file
diff --git a/src/DfE.CoreLibs.Testing/Mocks/WebApplicationFactory/CustomWebApplicationDbContextFactory.cs b/src/DfE.CoreLibs.Testing/Mocks/WebApplicationFactory/CustomWebApplicationDbContextFactory.cs
index 3ebf23a..0fddc4e 100644
--- a/src/DfE.CoreLibs.Testing/Mocks/WebApplicationFactory/CustomWebApplicationDbContextFactory.cs
+++ b/src/DfE.CoreLibs.Testing/Mocks/WebApplicationFactory/CustomWebApplicationDbContextFactory.cs
@@ -1,6 +1,7 @@
 using DfE.CoreLibs.Testing.Helpers;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.Data.Sqlite;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.DependencyInjection;
 using System.Data.Common;
@@ -13,7 +14,7 @@ namespace DfE.CoreLibs.Testing.Mocks.WebApplicationFactory
     public class CustomWebApplicationDbContextFactory<TProgram> : WebApplicationFactory<TProgram>
         where TProgram : class
     {
-        public List<Claim>? TestClaims { get; set; } = [];
+        public List<Claim>? TestClaims { get; set; } = new();
         public Dictionary<Type, Action<DbContext>>? SeedData { get; set; }
         public Action<IServiceCollection>? ExternalServicesConfiguration { get; set; }
         public Action<HttpClient>? ExternalHttpClientConfiguration { get; set; }
@@ -22,35 +23,23 @@ protected override void ConfigureWebHost(IWebHostBuilder builder)
         {
             builder.ConfigureServices(services =>
             {
+                RemoveDbContextAndConnectionServices(services);
 
-                var dbContextDescriptors = services
-                    .Where(d => d.ServiceType.IsGenericType && d.ServiceType.GetGenericTypeDefinition() == typeof(DbContextOptions<>))
-                    .ToList();
-                foreach (var dbContextDescriptor in dbContextDescriptors)
-                {
-                    services.Remove(dbContextDescriptor);
-                }
+                var connection = new SqliteConnection("DataSource=:memory:");
+                connection.Open();
+                services.AddSingleton(connection);
 
-                var dbConnectionDescriptor = services.SingleOrDefault(d => d.ServiceType == typeof(DbConnection));
-                if (dbConnectionDescriptor != null)
-                {
-                    services.Remove(dbConnectionDescriptor);
-                }
-
-                foreach (var entry in SeedData ?? [])
+                foreach (var entry in SeedData ?? new Dictionary<Type, Action<DbContext>>())
                 {
                     var dbContextType = entry.Key;
                     var seedAction = entry.Value;
-
                     var createDbContextMethod = typeof(DbContextHelper).GetMethod(nameof(DbContextHelper.CreateDbContext))
                         ?.MakeGenericMethod(dbContextType);
-
-                    createDbContextMethod?.Invoke(null, new object[] { services, seedAction });
+                    createDbContextMethod?.Invoke(null, new object[] { services, connection, seedAction });
                 }
 
                 ExternalServicesConfiguration?.Invoke(services);
-
-                services.AddSingleton<IEnumerable<Claim>>(sp => TestClaims ?? []);
+                services.AddSingleton<IEnumerable<Claim>>(sp => TestClaims ?? new());
             });
 
             builder.UseEnvironment("Development");
@@ -59,7 +48,6 @@ protected override void ConfigureWebHost(IWebHostBuilder builder)
         protected override void ConfigureClient(HttpClient client)
         {
             ExternalHttpClientConfiguration?.Invoke(client);
-
             base.ConfigureClient(client);
         }
 
@@ -70,5 +58,21 @@ public TDbContext GetDbContext<TDbContext>() where TDbContext : DbContext
             return scope.ServiceProvider.GetRequiredService<TDbContext>();
         }
 
+        private static void RemoveDbContextAndConnectionServices(IServiceCollection services)
+        {
+            var dbContextDescriptors = services
+                .Where(d => d.ServiceType.IsGenericType && d.ServiceType.GetGenericTypeDefinition() == typeof(DbContextOptions<>))
+                .ToList();
+            foreach (var dbContextDescriptor in dbContextDescriptors)
+            {
+                services.Remove(dbContextDescriptor);
+            }
+
+            var dbConnectionDescriptor = services.SingleOrDefault(d => d.ServiceType == typeof(DbConnection));
+            if (dbConnectionDescriptor != null)
+            {
+                services.Remove(dbConnectionDescriptor);
+            }
+        }
     }
 }