Index: Ringtoets/Common/src/Ringtoets.Common.Data/Hydraulics/HydraulicBoundaryDatabaseExtensions.cs
===================================================================
diff -u -r381345fcad26d313d3cfd5ccd3d1e131c1d5c379 -r0c7f559da0144b5ecf707274a21db465e0ee9b36
--- Ringtoets/Common/src/Ringtoets.Common.Data/Hydraulics/HydraulicBoundaryDatabaseExtensions.cs	(.../HydraulicBoundaryDatabaseExtensions.cs)	(revision 381345fcad26d313d3cfd5ccd3d1e131c1d5c379)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/Hydraulics/HydraulicBoundaryDatabaseExtensions.cs	(.../HydraulicBoundaryDatabaseExtensions.cs)	(revision 0c7f559da0144b5ecf707274a21db465e0ee9b36)
@@ -29,6 +29,25 @@
     public static class HydraulicBoundaryDatabaseExtensions
     {
         /// <summary>
+        /// Checks whether the hydraulic boundary database is coupled to a database file.
+        /// </summary>
+        /// <param name="hydraulicBoundaryDatabase">The hydraulic boundary database to check
+        /// for being coupled.</param>
+        /// <returns><c>true</c> if the hydraulic boundary database is coupled;
+        /// <c>false</c> otherwise.</returns>
+        /// <exception cref="ArgumentNullException">Thrown when
+        /// <paramref name="hydraulicBoundaryDatabase"/> is <c>null</c>.</exception>
+        public static bool IsCoupled(this HydraulicBoundaryDatabase hydraulicBoundaryDatabase)
+        {
+            if (hydraulicBoundaryDatabase == null)
+            {
+                throw new ArgumentNullException(nameof(hydraulicBoundaryDatabase));
+            }
+
+            return !string.IsNullOrEmpty(hydraulicBoundaryDatabase.FilePath);
+        }
+
+        /// <summary>
         /// Gets the preprocessor directory to be used during Hydra-Ring calculations.
         /// </summary>
         /// <param name="hydraulicBoundaryDatabase">The hydraulic boundary database to get the
Index: Ringtoets/Common/test/Ringtoets.Common.Data.Test/Hydraulics/HydraulicBoundaryDatabaseExtensionsTest.cs
===================================================================
diff -u -rfe55aedc4ccec24ea5827ecf23a965d2a2cb1ed8 -r0c7f559da0144b5ecf707274a21db465e0ee9b36
--- Ringtoets/Common/test/Ringtoets.Common.Data.Test/Hydraulics/HydraulicBoundaryDatabaseExtensionsTest.cs	(.../HydraulicBoundaryDatabaseExtensionsTest.cs)	(revision fe55aedc4ccec24ea5827ecf23a965d2a2cb1ed8)
+++ Ringtoets/Common/test/Ringtoets.Common.Data.Test/Hydraulics/HydraulicBoundaryDatabaseExtensionsTest.cs	(.../HydraulicBoundaryDatabaseExtensionsTest.cs)	(revision 0c7f559da0144b5ecf707274a21db465e0ee9b36)
@@ -29,6 +29,17 @@
     public class HydraulicBoundaryDatabaseExtensionsTest
     {
         [Test]
+        public void IsCoupled_HydraulicBoundaryDatabaseNull_ThrowsArgumentNullException()
+        {
+            // Call
+            TestDelegate test = () => HydraulicBoundaryDatabaseExtensions.IsCoupled(null);
+
+            // Assert
+            string paramName = Assert.Throws<ArgumentNullException>(test).ParamName;
+            Assert.AreEqual("hydraulicBoundaryDatabase", paramName);
+        }
+
+        [Test]
         public void EffectivePreprocessorDirectory_HydraulicBoundaryDatabaseNull_ThrowsArgumentNullException()
         {
             // Call
@@ -52,6 +63,24 @@
             Assert.AreEqual("", effectivePreprocessorDirectory);
         }
 
+        [TestCase(null, false)]
+        [TestCase("", false)]
+        [TestCase("Test", true)]
+        public void IsCoupled_SpecificFilePath_ReturnsExpectedValue(string filePath, bool expectedValue)
+        {
+            // Setup
+            var hydraulicBoundaryDatabase = new HydraulicBoundaryDatabase
+            {
+                FilePath = filePath
+            };
+
+            // Call
+            bool isCoupled = hydraulicBoundaryDatabase.IsCoupled();
+
+            // Assert
+            Assert.AreEqual(expectedValue, isCoupled);
+        }
+
         [TestCase(false, "Test", "")]
         [TestCase(true, "Test", "Test")]
         public void EffectivePreprocessorDirectory_CanUsePreprocessorTrue_ReturnsExpectedValue(bool usePreprocessor,